diff --git a/Notebooks/Chap07/7_1_Backpropagation_in_Toy_Model.ipynb b/Notebooks/Chap07/7_1_Backpropagation_in_Toy_Model.ipynb
index d6924b0..a9eb38b 100644
--- a/Notebooks/Chap07/7_1_Backpropagation_in_Toy_Model.ipynb
+++ b/Notebooks/Chap07/7_1_Backpropagation_in_Toy_Model.ipynb
@@ -4,7 +4,7 @@
   "metadata": {
     "colab": {
       "provenance": [],
-      "authorship_tag": "ABX9TyOjXmTmoff61y15VqEB5sDW",
+      "authorship_tag": "ABX9TyN7JeDgslwtZcwRCOuGuPFt",
       "include_colab_link": true
     },
     "kernelspec": {
@@ -83,7 +83,7 @@
       "metadata": {
         "id": "RIPaoVN834Lj"
       },
-      "execution_count": 1,
+      "execution_count": null,
       "outputs": []
     },
     {
@@ -97,7 +97,7 @@
     },
     {
       "cell_type": "code",
-      "execution_count": 2,
+      "execution_count": null,
       "metadata": {
         "id": "AakK_qen3BpU"
       },
@@ -136,7 +136,7 @@
         },
         "outputId": "9541922c-dfc4-4b2e-dfa3-3298812155ce"
       },
-      "execution_count": 3,
+      "execution_count": null,
       "outputs": [
         {
           "output_type": "stream",
@@ -175,7 +175,7 @@
       "metadata": {
         "id": "7t22hALp5zkq"
       },
-      "execution_count": 4,
+      "execution_count": null,
       "outputs": []
     },
     {
@@ -201,7 +201,7 @@
         },
         "outputId": "389ed78e-9d8d-4e8b-9e6b-5f20c21407e8"
       },
-      "execution_count": 5,
+      "execution_count": null,
       "outputs": [
         {
           "output_type": "stream",
@@ -261,7 +261,7 @@
       "metadata": {
         "id": "ZWKAq6HC90qV"
       },
-      "execution_count": 6,
+      "execution_count": null,
       "outputs": []
     },
     {
@@ -284,7 +284,7 @@
         },
         "outputId": "4575e3eb-2b16-4e0b-c84e-9c22b443c3ce"
       },
-      "execution_count": 7,
+      "execution_count": null,
       "outputs": [
         {
           "output_type": "stream",
@@ -362,7 +362,7 @@
       "metadata": {
         "id": "gCQJeI--Egdl"
       },
-      "execution_count": 8,
+      "execution_count": null,
       "outputs": []
     },
     {
@@ -384,7 +384,7 @@
         },
         "outputId": "414f0862-ae36-4a0e-b68f-4758835b0e23"
       },
-      "execution_count": 9,
+      "execution_count": null,
       "outputs": [
         {
           "output_type": "stream",
@@ -414,7 +414,7 @@
         "\\frac{\\partial \\ell_i}{\\partial \\omega_{k}} &=& \\frac{\\partial f_{k}}{\\partial \\omega_{k}}\\frac{\\partial \\ell_i}{\\partial f_{k}}.\n",
         "\\end{eqnarray}\n",
         "\n",
-        "\\noindent In each case, the second term on the right-hand side was computed in step 2. When $k>0$, we have~$f_{k}=\\beta_{k}+\\omega_k \\cdot h_{k}$, so:\n",
+        "In each case, the second term on the right-hand side was computed in step 2. When $k>0$, we have~$f_{k}=\\beta_{k}+\\omega_k \\cdot h_{k}$, so:\n",
         "\n",
         "\\begin{eqnarray}\n",
         "\\frac{\\partial f_{k}}{\\partial \\beta_{k}} = 1 \\quad\\quad\\mbox{and}\\quad \\quad \\frac{\\partial f_{k}}{\\partial \\omega_{k}} &=& h_{k}.\n",
@@ -441,7 +441,7 @@
       "metadata": {
         "id": "1I2BhqZhGMK6"
       },
-      "execution_count": 10,
+      "execution_count": null,
       "outputs": []
     },
     {
@@ -464,7 +464,7 @@
         },
         "outputId": "1a67a636-e832-471e-e771-54824363158a"
       },
-      "execution_count": 11,
+      "execution_count": null,
       "outputs": [
         {
           "output_type": "stream",