diff --git a/100_Numpy_exercises.ipynb b/100_Numpy_exercises.ipynb
index 3722882..db8c742 100644
--- a/100_Numpy_exercises.ipynb
+++ b/100_Numpy_exercises.ipynb
@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "markdown",
-   "id": "3780a226",
+   "id": "cf1ef34b",
    "metadata": {},
    "source": [
     "# 100 numpy exercises\n",
@@ -18,7 +18,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "63ded581",
+   "id": "6f6230b6",
    "metadata": {},
    "source": [
     "File automatically generated. See the documentation to update questions/answers/hints programmatically."
@@ -26,17 +26,17 @@
   },
   {
    "cell_type": "markdown",
-   "id": "456258e7",
+   "id": "699bb7c8",
    "metadata": {},
    "source": [
-    "Run the `initialize.py` module, then for each question you can query the\n",
+    "Run the `initialise.py` module, then for each question you can query the\n",
     "answer or an hint with `hint(n)` or `answer(n)` for `n` question number."
    ]
   },
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "ad8f85b1",
+   "id": "f8766b32",
    "metadata": {},
    "outputs": [],
    "source": [
@@ -45,7 +45,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "40518c2e",
+   "id": "86bb254b",
    "metadata": {},
    "source": [
     "#### 1. Import the numpy package under the name `np` (★☆☆)"
@@ -54,14 +54,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "08ee02d9",
+   "id": "518c8183",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "47c48198",
+   "id": "73bc1295",
    "metadata": {},
    "source": [
     "#### 2. Print the numpy version and the configuration (★☆☆)"
@@ -70,14 +70,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "8a94ff73",
+   "id": "cc208209",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "4f405544",
+   "id": "3ec5eeae",
    "metadata": {},
    "source": [
     "#### 3. Create a null vector of size 10 (★☆☆)"
@@ -86,14 +86,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4a0d86fc",
+   "id": "11ac0188",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "c8754c7a",
+   "id": "4833b037",
    "metadata": {},
    "source": [
     "#### 4. How to find the memory size of any array (★☆☆)"
@@ -102,14 +102,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4fa4c3e1",
+   "id": "7b37d02c",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "0381891d",
+   "id": "22406ea1",
    "metadata": {},
    "source": [
     "#### 5. How to get the documentation of the numpy add function from the command line? (★☆☆)"
@@ -118,14 +118,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "79c56ec6",
+   "id": "17cd71af",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "fb0edf87",
+   "id": "b3ab3c55",
    "metadata": {},
    "source": [
     "#### 6. Create a null vector of size 10 but the fifth value which is 1 (★☆☆)"
@@ -134,14 +134,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "5b8c3d98",
+   "id": "0b6c7f75",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "6aedaa04",
+   "id": "6d8c00c9",
    "metadata": {},
    "source": [
     "#### 7. Create a vector with values ranging from 10 to 49 (★☆☆)"
@@ -150,14 +150,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "399d0f91",
+   "id": "ba0eea70",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "c05183de",
+   "id": "eef0d721",
    "metadata": {},
    "source": [
     "#### 8. Reverse a vector (first element becomes last) (★☆☆)"
@@ -166,14 +166,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "beb3ed87",
+   "id": "e73e011f",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "49ffe24b",
+   "id": "bf274738",
    "metadata": {},
    "source": [
     "#### 9. Create a 3x3 matrix with values ranging from 0 to 8 (★☆☆)"
@@ -182,14 +182,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "6bcbb69c",
+   "id": "0013166a",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "d74c5259",
+   "id": "edc4900b",
    "metadata": {},
    "source": [
     "#### 10. Find indices of non-zero elements from [1,2,0,0,4,0] (★☆☆)"
@@ -198,14 +198,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "5a70a7b4",
+   "id": "5ec949de",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "8a986270",
+   "id": "8f68dabf",
    "metadata": {},
    "source": [
     "#### 11. Create a 3x3 identity matrix (★☆☆)"
@@ -214,14 +214,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "c681b2ae",
+   "id": "65bf9ac5",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "b024a4bf",
+   "id": "f740ed30",
    "metadata": {},
    "source": [
     "#### 12. Create a 3x3x3 array with random values (★☆☆)"
@@ -230,14 +230,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "e7b54796",
+   "id": "2e6a02fa",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "629c0620",
+   "id": "0befba5c",
    "metadata": {},
    "source": [
     "#### 13. Create a 10x10 array with random values and find the minimum and maximum values (★☆☆)"
@@ -246,14 +246,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "0f12525b",
+   "id": "76c90ded",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "25f9f091",
+   "id": "98d22f5c",
    "metadata": {},
    "source": [
     "#### 14. Create a random vector of size 30 and find the mean value (★☆☆)"
@@ -262,14 +262,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "03dce2ff",
+   "id": "462c67ff",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "9c4ac621",
+   "id": "9aa941ad",
    "metadata": {},
    "source": [
     "#### 15. Create a 2d array with 1 on the border and 0 inside (★☆☆)"
@@ -278,14 +278,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "0a811a3b",
+   "id": "800e919d",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "c0110caf",
+   "id": "bb1fedb7",
    "metadata": {},
    "source": [
     "#### 16. How to add a border (filled with 0's) around an existing array? (★☆☆)"
@@ -294,14 +294,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "5e461b43",
+   "id": "a7db7847",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "c097faee",
+   "id": "650e107f",
    "metadata": {},
    "source": [
     "#### 17. What is the result of the following expression? (★☆☆)\n",
@@ -318,14 +318,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "de307b6d",
+   "id": "16163e87",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "7539be84",
+   "id": "212a2d9e",
    "metadata": {},
    "source": [
     "#### 18. Create a 5x5 matrix with values 1,2,3,4 just below the diagonal (★☆☆)"
@@ -334,14 +334,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "897eeebd",
+   "id": "8fb12d05",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "69207418",
+   "id": "38c8a0b8",
    "metadata": {},
    "source": [
     "#### 19. Create a 8x8 matrix and fill it with a checkerboard pattern (★☆☆)"
@@ -350,14 +350,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "da9fc94e",
+   "id": "73de81c7",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "aeb836d2",
+   "id": "a298d56c",
    "metadata": {},
    "source": [
     "#### 20. Consider a (6,7,8) shape array, what is the index (x,y,z) of the 100th element? (★☆☆)"
@@ -366,14 +366,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "c026c791",
+   "id": "06bd3ad1",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "9aef01d6",
+   "id": "bf247eb3",
    "metadata": {},
    "source": [
     "#### 21. Create a checkerboard 8x8 matrix using the tile function (★☆☆)"
@@ -382,14 +382,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "1cdf747e",
+   "id": "40f5f51a",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "931830f8",
+   "id": "4111e5bf",
    "metadata": {},
    "source": [
     "#### 22. Normalize a 5x5 random matrix (★☆☆)"
@@ -398,14 +398,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "1d081cd3",
+   "id": "845e0a38",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "5f3b5379",
+   "id": "711631f6",
    "metadata": {},
    "source": [
     "#### 23. Create a custom dtype that describes a color as four unsigned bytes (RGBA) (★☆☆)"
@@ -414,14 +414,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "56847b08",
+   "id": "05c4f307",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "27294dd6",
+   "id": "f6b0e3fe",
    "metadata": {},
    "source": [
     "#### 24. Multiply a 5x3 matrix by a 3x2 matrix (real matrix product) (★☆☆)"
@@ -430,14 +430,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "5b219d77",
+   "id": "f92bc78d",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "57a463f5",
+   "id": "39a05eb5",
    "metadata": {},
    "source": [
     "#### 25. Given a 1D array, negate all elements which are between 3 and 8, in place. (★☆☆)"
@@ -446,14 +446,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "1137097c",
+   "id": "1a92f1c1",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "4ec37bca",
+   "id": "d4605cfb",
    "metadata": {},
    "source": [
     "#### 26. What is the output of the following script? (★☆☆)\n",
@@ -469,14 +469,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "ae0f3d30",
+   "id": "22f602e0",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "fb875416",
+   "id": "affc0180",
    "metadata": {},
    "source": [
     "#### 27. Consider an integer vector Z, which of these expressions are legal? (★☆☆)\n",
@@ -493,14 +493,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "0b516d7c",
+   "id": "e288ada9",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "3322bcc4",
+   "id": "b18a40e7",
    "metadata": {},
    "source": [
     "#### 28. What are the result of the following expressions? (★☆☆)\n",
@@ -514,14 +514,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "68a40ed3",
+   "id": "169a8c58",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "e85dae57",
+   "id": "c2e6fa83",
    "metadata": {},
    "source": [
     "#### 29. How to round away from zero a float array ? (★☆☆)"
@@ -530,14 +530,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "8981d8e2",
+   "id": "883fd972",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "3d78851a",
+   "id": "77285ae7",
    "metadata": {},
    "source": [
     "#### 30. How to find common values between two arrays? (★☆☆)"
@@ -546,14 +546,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "ca4b0788",
+   "id": "37922693",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "535563a3",
+   "id": "0a0c4dc3",
    "metadata": {},
    "source": [
     "#### 31. How to ignore all numpy warnings (not recommended)? (★☆☆)"
@@ -562,14 +562,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "b1884a9f",
+   "id": "e9d40845",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "9ff18333",
+   "id": "4700d906",
    "metadata": {},
    "source": [
     "#### 32. Is the following expressions true? (★☆☆)\n",
@@ -581,14 +581,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "b47e3ad5",
+   "id": "40a41109",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "94dfbdcb",
+   "id": "a3ef25bc",
    "metadata": {},
    "source": [
     "#### 33. How to get the dates of yesterday, today and tomorrow? (★☆☆)"
@@ -597,14 +597,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "3f686831",
+   "id": "ed7abca1",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "eb1816a2",
+   "id": "4d2a3667",
    "metadata": {},
    "source": [
     "#### 34. How to get all the dates corresponding to the month of July 2016? (★★☆)"
@@ -613,14 +613,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "963239fb",
+   "id": "ffd619f0",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "9174632a",
+   "id": "e8df2961",
    "metadata": {},
    "source": [
     "#### 35. How to compute ((A+B)*(-A/2)) in place (without copy)? (★★☆)"
@@ -629,14 +629,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "660f5868",
+   "id": "0399883a",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "b6b4504d",
+   "id": "9f117716",
    "metadata": {},
    "source": [
     "#### 36. Extract the integer part of a random array of positive numbers using 4 different methods (★★☆)"
@@ -645,14 +645,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "a125254d",
+   "id": "eea97bde",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "dcd769b0",
+   "id": "ce178ee0",
    "metadata": {},
    "source": [
     "#### 37. Create a 5x5 matrix with row values ranging from 0 to 4 (★★☆)"
@@ -661,14 +661,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "6e5f39c8",
+   "id": "a3d9f792",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "83642768",
+   "id": "0f4ea1a0",
    "metadata": {},
    "source": [
     "#### 38. Consider a generator function that generates 10 integers and use it to build an array (★☆☆)"
@@ -677,14 +677,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "a24bdb56",
+   "id": "8da1da7a",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "8ab76708",
+   "id": "7f47a1a7",
    "metadata": {},
    "source": [
     "#### 39. Create a vector of size 10 with values ranging from 0 to 1, both excluded (★★☆)"
@@ -693,14 +693,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "2b66dc48",
+   "id": "bc941b22",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "a77ffeff",
+   "id": "cda5555a",
    "metadata": {},
    "source": [
     "#### 40. Create a random vector of size 10 and sort it (★★☆)"
@@ -709,14 +709,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4bd4613d",
+   "id": "0b131978",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "0f131622",
+   "id": "fcb4f465",
    "metadata": {},
    "source": [
     "#### 41. How to sum a small array faster than np.sum? (★★☆)"
@@ -725,14 +725,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "50006b4f",
+   "id": "060223c0",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "0205ef5d",
+   "id": "3c3d7234",
    "metadata": {},
    "source": [
     "#### 42. Consider two random arrays A and B, check if they are equal (★★☆)"
@@ -741,14 +741,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "33df1c36",
+   "id": "f499fcc0",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "be053e5d",
+   "id": "d99f6e03",
    "metadata": {},
    "source": [
     "#### 43. Make an array immutable (read-only) (★★☆)"
@@ -757,14 +757,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "060a0518",
+   "id": "69eccc3a",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "92732bec",
+   "id": "def920df",
    "metadata": {},
    "source": [
     "#### 44. Consider a random 10x2 matrix representing cartesian coordinates, convert them to polar coordinates (★★☆)"
@@ -773,14 +773,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "d4f46c96",
+   "id": "515f464d",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "1f75774a",
+   "id": "055ebe42",
    "metadata": {},
    "source": [
     "#### 45. Create random vector of size 10 and replace the maximum value by 0 (★★☆)"
@@ -789,14 +789,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "812354bf",
+   "id": "bb1f0772",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "ed8431ad",
+   "id": "620bc824",
    "metadata": {},
    "source": [
     "#### 46. Create a structured array with `x` and `y` coordinates covering the [0,1]x[0,1] area (★★☆)"
@@ -805,14 +805,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "f0966336",
+   "id": "e5e11349",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "34250c0f",
+   "id": "94ea37a2",
    "metadata": {},
    "source": [
     "#### 47. Given two arrays, X and Y, construct the Cauchy matrix C (Cij =1/(xi - yj)) (★★☆)"
@@ -821,14 +821,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "e8a7ac1a",
+   "id": "2f17ac46",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "5418176b",
+   "id": "00b3d6c7",
    "metadata": {},
    "source": [
     "#### 48. Print the minimum and maximum representable values for each numpy scalar type (★★☆)"
@@ -837,14 +837,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "ad633154",
+   "id": "b3fe7fae",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "1d868ac4",
+   "id": "222a56bf",
    "metadata": {},
    "source": [
     "#### 49. How to print all the values of an array? (★★☆)"
@@ -853,14 +853,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "d12c9111",
+   "id": "ef470264",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "c5f1c082",
+   "id": "df13c8c7",
    "metadata": {},
    "source": [
     "#### 50. How to find the closest value (to a given scalar) in a vector? (★★☆)"
@@ -869,14 +869,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4374f950",
+   "id": "cdc407d4",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "91d0c841",
+   "id": "37d46c4c",
    "metadata": {},
    "source": [
     "#### 51. Create a structured array representing a position (x,y) and a color (r,g,b) (★★☆)"
@@ -885,14 +885,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "11b8fc88",
+   "id": "8aa81f1c",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "076d36d7",
+   "id": "b628672c",
    "metadata": {},
    "source": [
     "#### 52. Consider a random vector with shape (100,2) representing coordinates, find point by point distances (★★☆)"
@@ -901,14 +901,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "14c1ff07",
+   "id": "72bc8a0c",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "3581ca30",
+   "id": "4087a52b",
    "metadata": {},
    "source": [
     "#### 53. How to convert a float (32 bits) array into an integer (32 bits) array in place?"
@@ -917,14 +917,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "72732a66",
+   "id": "d6420a26",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "3f440ff2",
+   "id": "07ee5bc1",
    "metadata": {},
    "source": [
     "#### 54. How to read the following file? (★★☆)\n",
@@ -938,14 +938,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "9d03d55d",
+   "id": "0d0a20a3",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "8ef1aff5",
+   "id": "3c0faef9",
    "metadata": {},
    "source": [
     "#### 55. What is the equivalent of enumerate for numpy arrays? (★★☆)"
@@ -954,14 +954,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "bc1cfb8e",
+   "id": "646e9f61",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "b8737694",
+   "id": "99cbb1dd",
    "metadata": {},
    "source": [
     "#### 56. Generate a generic 2D Gaussian-like array (★★☆)"
@@ -970,14 +970,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "e38c976d",
+   "id": "3b127842",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "1f7a093e",
+   "id": "976e8fed",
    "metadata": {},
    "source": [
     "#### 57. How to randomly place p elements in a 2D array? (★★☆)"
@@ -986,14 +986,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "aa14eab2",
+   "id": "aced8bc6",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "4b1f4144",
+   "id": "e263430b",
    "metadata": {},
    "source": [
     "#### 58. Subtract the mean of each row of a matrix (★★☆)"
@@ -1002,14 +1002,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "39be0ed4",
+   "id": "b8422f36",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "36c47776",
+   "id": "65245363",
    "metadata": {},
    "source": [
     "#### 59. How to sort an array by the nth column? (★★☆)"
@@ -1018,14 +1018,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "43867c6a",
+   "id": "4738c884",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "d798a57f",
+   "id": "0ebe0c25",
    "metadata": {},
    "source": [
     "#### 60. How to tell if a given 2D array has null columns? (★★☆)"
@@ -1034,14 +1034,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "d2059b5c",
+   "id": "852bbd9c",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "eee145c4",
+   "id": "7edfc14e",
    "metadata": {},
    "source": [
     "#### 61. Find the nearest value from a given value in an array (★★☆)"
@@ -1050,14 +1050,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "1b1b5829",
+   "id": "15c7dd5f",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "745bdd9a",
+   "id": "e91490a4",
    "metadata": {},
    "source": [
     "#### 62. Considering two arrays with shape (1,3) and (3,1), how to compute their sum using an iterator? (★★☆)"
@@ -1066,14 +1066,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "3a9859f9",
+   "id": "77a5759d",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "652b80f0",
+   "id": "0521e979",
    "metadata": {},
    "source": [
     "#### 63. Create an array class that has a name attribute (★★☆)"
@@ -1082,14 +1082,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "cfe2e2a7",
+   "id": "2d13bf65",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "58349a3a",
+   "id": "621a1a83",
    "metadata": {},
    "source": [
     "#### 64. Consider a given vector, how to add 1 to each element indexed by a second vector (be careful with repeated indices)? (★★★)"
@@ -1098,14 +1098,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "7d5f94a6",
+   "id": "2b68677b",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "13247c07",
+   "id": "a14a48d7",
    "metadata": {},
    "source": [
     "#### 65. How to accumulate elements of a vector (X) to an array (F) based on an index list (I)? (★★★)"
@@ -1114,14 +1114,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "074b5598",
+   "id": "e2f51a24",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "8996b4be",
+   "id": "39519e19",
    "metadata": {},
    "source": [
     "#### 66. Considering a (w,h,3) image of (dtype=ubyte), compute the number of unique colors (★★☆)"
@@ -1130,14 +1130,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4541bada",
+   "id": "24e2c766",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "1de1a251",
+   "id": "71fb8c01",
    "metadata": {},
    "source": [
     "#### 67. Considering a four dimensions array, how to get sum over the last two axis at once? (★★★)"
@@ -1146,14 +1146,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "855d4734",
+   "id": "df855378",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "2c3a49fa",
+   "id": "f21b484a",
    "metadata": {},
    "source": [
     "#### 68. Considering a one-dimensional vector D, how to compute means of subsets of D using a vector S of same size describing subset  indices? (★★★)"
@@ -1162,14 +1162,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "9785a70e",
+   "id": "19ddb0ea",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "d97e5ce6",
+   "id": "2190b0f6",
    "metadata": {},
    "source": [
     "#### 69. How to get the diagonal of a dot product? (★★★)"
@@ -1178,14 +1178,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "b8adf4c7",
+   "id": "7ee08c89",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "59f04026",
+   "id": "59ad47ed",
    "metadata": {},
    "source": [
     "#### 70. Consider the vector [1, 2, 3, 4, 5], how to build a new vector with 3 consecutive zeros interleaved between each value? (★★★)"
@@ -1194,14 +1194,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "9bf72549",
+   "id": "adc755f1",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "5915be32",
+   "id": "5c637715",
    "metadata": {},
    "source": [
     "#### 71. Consider an array of dimension (5,5,3), how to multiply it by an array with dimensions (5,5)? (★★★)"
@@ -1210,14 +1210,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "615685a1",
+   "id": "650cc21f",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "88afd68d",
+   "id": "d586e715",
    "metadata": {},
    "source": [
     "#### 72. How to swap two rows of an array? (★★★)"
@@ -1226,14 +1226,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "ab382690",
+   "id": "c7b20b67",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "103b64e3",
+   "id": "6f411566",
    "metadata": {},
    "source": [
     "#### 73. Consider a set of 10 triplets describing 10 triangles (with shared vertices), find the set of unique line segments composing all the  triangles (★★★)"
@@ -1242,14 +1242,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "ea64e9b8",
+   "id": "609122b8",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "69e0c2c7",
+   "id": "59807176",
    "metadata": {},
    "source": [
     "#### 74. Given a sorted array C that corresponds to a bincount, how to produce an array A such that np.bincount(A) == C? (★★★)"
@@ -1258,14 +1258,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "7935210d",
+   "id": "81663875",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "a217bfc5",
+   "id": "5146bc0c",
    "metadata": {},
    "source": [
     "#### 75. How to compute averages using a sliding window over an array? (★★★)"
@@ -1274,14 +1274,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "16cd9bde",
+   "id": "d5d875cd",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "1da33793",
+   "id": "58e73426",
    "metadata": {},
    "source": [
     "#### 76. Consider a one-dimensional array Z, build a two-dimensional array whose first row is (Z[0],Z[1],Z[2]) and each subsequent row is  shifted by 1 (last row should be (Z[-3],Z[-2],Z[-1]) (★★★)"
@@ -1290,14 +1290,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "8059a53b",
+   "id": "fa414aab",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "f6c798af",
+   "id": "1ed1562b",
    "metadata": {},
    "source": [
     "#### 77. How to negate a boolean, or to change the sign of a float inplace? (★★★)"
@@ -1306,14 +1306,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "95d52799",
+   "id": "5635bb46",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "ed6b13c8",
+   "id": "0bdf5738",
    "metadata": {},
    "source": [
     "#### 78. Consider 2 sets of points P0,P1 describing lines (2d) and a point p, how to compute distance from p to each line i (P0[i],P1[i])? (★★★)"
@@ -1322,14 +1322,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "2870e6b4",
+   "id": "1b40ceda",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "7f9a94ca",
+   "id": "d6b2a570",
    "metadata": {},
    "source": [
     "#### 79. Consider 2 sets of points P0,P1 describing lines (2d) and a set of points P, how to compute distance from each point j (P[j]) to each line i (P0[i],P1[i])? (★★★)"
@@ -1338,14 +1338,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "de27d0c4",
+   "id": "e74d9556",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "61709616",
+   "id": "10a26db0",
    "metadata": {},
    "source": [
     "#### 80. Consider an arbitrary array, write a function that extracts a subpart with a fixed shape and centered on a given element (pad with a `fill` value when necessary) (★★★)"
@@ -1354,14 +1354,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "952b826a",
+   "id": "51453c36",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "585a0296",
+   "id": "0b16fd78",
    "metadata": {},
    "source": [
     "#### 81. Consider an array Z = [1,2,3,4,5,6,7,8,9,10,11,12,13,14], how to generate an array R = [[1,2,3,4], [2,3,4,5], [3,4,5,6], ..., [11,12,13,14]]? (★★★)"
@@ -1370,14 +1370,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "66729fa0",
+   "id": "22744f52",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "f6ea03b3",
+   "id": "32d8f28c",
    "metadata": {},
    "source": [
     "#### 82. Compute a matrix rank (★★★)"
@@ -1386,14 +1386,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "80b6d0f4",
+   "id": "3ee2a152",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "1ef1692e",
+   "id": "cb129ead",
    "metadata": {},
    "source": [
     "#### 83. How to find the most frequent value in an array?"
@@ -1402,14 +1402,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "de8f66cc",
+   "id": "c6f253a6",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "310aa04e",
+   "id": "3035e42a",
    "metadata": {},
    "source": [
     "#### 84. Extract all the contiguous 3x3 blocks from a random 10x10 matrix (★★★)"
@@ -1418,14 +1418,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "f2639e17",
+   "id": "778e4127",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "cdf46958",
+   "id": "692fb35b",
    "metadata": {},
    "source": [
     "#### 85. Create a 2D array subclass such that Z[i,j] == Z[j,i] (★★★)"
@@ -1434,14 +1434,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "7f3cb2c9",
+   "id": "36ae4368",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "9ab6b1ca",
+   "id": "5412edce",
    "metadata": {},
    "source": [
     "#### 86. Consider a set of p matrices with shape (n,n) and a set of p vectors with shape (n,1). How to compute the sum of of the p matrix products at once? (result has shape (n,1)) (★★★)"
@@ -1450,14 +1450,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "a6f93a7b",
+   "id": "cbb9912f",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "2c8cd60e",
+   "id": "d6953705",
    "metadata": {},
    "source": [
     "#### 87. Consider a 16x16 array, how to get the block-sum (block size is 4x4)? (★★★)"
@@ -1466,14 +1466,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "1f8d7f5f",
+   "id": "8e4fa063",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "cbd5321e",
+   "id": "e31ffc63",
    "metadata": {},
    "source": [
     "#### 88. How to implement the Game of Life using numpy arrays? (★★★)"
@@ -1482,14 +1482,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "a8bd84fd",
+   "id": "bcd9e5ed",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "f9c4b416",
+   "id": "364c7e98",
    "metadata": {},
    "source": [
     "#### 89. How to get the n largest values of an array (★★★)"
@@ -1498,14 +1498,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "c4123ace",
+   "id": "b5e5a5d9",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "495897e7",
+   "id": "98eb9cb6",
    "metadata": {},
    "source": [
     "#### 90. Given an arbitrary number of vectors, build the cartesian product (every combination of every item) (★★★)"
@@ -1514,14 +1514,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "9a9ed4a7",
+   "id": "fee613f4",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "c26bde0b",
+   "id": "6d934720",
    "metadata": {},
    "source": [
     "#### 91. How to create a record array from a regular array? (★★★)"
@@ -1530,14 +1530,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4958f3a6",
+   "id": "b5d5f153",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "d6c5435c",
+   "id": "db2fc6ec",
    "metadata": {},
    "source": [
     "#### 92. Consider a large vector Z, compute Z to the power of 3 using 3 different methods (★★★)"
@@ -1546,14 +1546,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "5269d1ec",
+   "id": "df435ed9",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "9f7efc22",
+   "id": "112fddd0",
    "metadata": {},
    "source": [
     "#### 93. Consider two arrays A and B of shape (8,3) and (2,2). How to find rows of A that contain elements of each row of B regardless of the order of the elements in B? (★★★)"
@@ -1562,14 +1562,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "1d9166aa",
+   "id": "911ccb7e",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "2bfe9e3c",
+   "id": "b0e62e04",
    "metadata": {},
    "source": [
     "#### 94. Considering a 10x3 matrix, extract rows with unequal values (e.g. [2,2,3]) (★★★)"
@@ -1578,14 +1578,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "c00f8f84",
+   "id": "2359edad",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "1bebee22",
+   "id": "79b7f023",
    "metadata": {},
    "source": [
     "#### 95. Convert a vector of ints into a matrix binary representation (★★★)"
@@ -1594,14 +1594,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4bf1b73f",
+   "id": "7fd3d80e",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "37acca61",
+   "id": "801babdf",
    "metadata": {},
    "source": [
     "#### 96. Given a two dimensional array, how to extract unique rows? (★★★)"
@@ -1610,14 +1610,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "7051b1d7",
+   "id": "e3f8e896",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "6c8a313c",
+   "id": "5e447828",
    "metadata": {},
    "source": [
     "#### 97. Considering 2 vectors A & B, write the einsum equivalent of inner, outer, sum, and mul function (★★★)"
@@ -1626,14 +1626,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "7bb32dd1",
+   "id": "3c6e497c",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "dffed116",
+   "id": "9e5a85e0",
    "metadata": {},
    "source": [
     "#### 98. Considering a path described by two vectors (X,Y), how to sample it using equidistant samples (★★★)?"
@@ -1642,14 +1642,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "c8a0a05f",
+   "id": "9643a618",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "e2208f4e",
+   "id": "8d305a59",
    "metadata": {},
    "source": [
     "#### 99. Given an integer n and a 2D array X, select from X the rows which can be interpreted as draws from a multinomial distribution with n degrees, i.e., the rows which only contain integers and which sum to n. (★★★)"
@@ -1658,14 +1658,14 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "5a240dba",
+   "id": "eb6b9159",
    "metadata": {},
    "outputs": [],
    "source": []
   },
   {
    "cell_type": "markdown",
-   "id": "21157036",
+   "id": "6e2b83fc",
    "metadata": {},
    "source": [
     "#### 100. Compute bootstrapped 95% confidence intervals for the mean of a 1D array X (i.e., resample the elements of an array with replacement N times, compute the mean of each sample, and then compute percentiles over the means). (★★★)"
@@ -1674,7 +1674,7 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "66c8a5db",
+   "id": "76d6be8f",
    "metadata": {},
    "outputs": [],
    "source": []
diff --git a/100_Numpy_exercises_with_hints_with_solutions.md b/100_Numpy_exercises_with_hints_with_solutions.md
index 409c00f..633ef1f 100644
--- a/100_Numpy_exercises_with_hints_with_solutions.md
+++ b/100_Numpy_exercises_with_hints_with_solutions.md
@@ -993,7 +993,8 @@ print(sliding_window_view(Z, window_shape=4))
 
 Z = np.random.uniform(0,1,(10,10))
 U, S, V = np.linalg.svd(Z) # Singular Value Decomposition
-rank = np.sum(S > 1e-10)
+threshold = len(S) * S.max() * np.finfo(S.dtype).eps
+rank = np.sum(S > threshold)
 print(rank)
 
 # alternative solution:
diff --git a/100_Numpy_exercises_with_solutions.md b/100_Numpy_exercises_with_solutions.md
index c7285d2..352c272 100644
--- a/100_Numpy_exercises_with_solutions.md
+++ b/100_Numpy_exercises_with_solutions.md
@@ -993,7 +993,8 @@ print(sliding_window_view(Z, window_shape=4))
 
 Z = np.random.uniform(0,1,(10,10))
 U, S, V = np.linalg.svd(Z) # Singular Value Decomposition
-rank = np.sum(S > 1e-10)
+threshold = len(S) * S.max() * np.finfo(S.dtype).eps
+rank = np.sum(S > threshold)
 print(rank)
 
 # alternative solution:
diff --git a/100_Numpy_random.ipynb b/100_Numpy_random.ipynb
index 880138a..bf3c433 100644
--- a/100_Numpy_random.ipynb
+++ b/100_Numpy_random.ipynb
@@ -2,7 +2,7 @@
  "cells": [
   {
    "cell_type": "markdown",
-   "id": "738eba3f",
+   "id": "c2a7dc72",
    "metadata": {},
    "source": [
     "# 100 numpy exercises\n",
@@ -18,7 +18,7 @@
   },
   {
    "cell_type": "markdown",
-   "id": "f65f901e",
+   "id": "0f9c3a25",
    "metadata": {},
    "source": [
     "File automatically generated. See the documentation to update questions/answers/hints programmatically."
@@ -26,17 +26,17 @@
   },
   {
    "cell_type": "markdown",
-   "id": "15045647",
+   "id": "7334326e",
    "metadata": {},
    "source": [
-    "Run the `initialize.py` module, then call a random question with `pick()` an hint towards its solution with\n",
+    "Run the `initialise.py` module, then call a random question with `pick()` an hint towards its solution with\n",
     "`hint(n)` and the answer with `answer(n)`, where n is the number of the picked question."
    ]
   },
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "0d23aa5b",
+   "id": "abd0d1b2",
    "metadata": {},
    "outputs": [],
    "source": [
@@ -46,7 +46,7 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "4a6a613b",
+   "id": "ecfa16ec",
    "metadata": {},
    "outputs": [],
    "source": [