diff --git a/tutorials/20260622164035_Let's Build a Quant Trading Strategy, MemLabs/part1.ipynb b/tutorials/20260622164035_Let's Build a Quant Trading Strategy, MemLabs/part1.ipynb
index 2cfbe57..d19b11c 100644
--- a/tutorials/20260622164035_Let's Build a Quant Trading Strategy, MemLabs/part1.ipynb	
+++ b/tutorials/20260622164035_Let's Build a Quant Trading Strategy, MemLabs/part1.ipynb	
@@ -370,11 +370,139 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 14,
    "id": "fe1ac560",
    "metadata": {},
-   "outputs": [],
-   "source": []
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
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+       "</style>\n",
+       "<div id=\"altair-viz-a919d4e55b4442d5b2b612267114813a\"></div>\n",
+       "<script type=\"text/javascript\">\n",
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+       "    const paths = {\n",
+       "      \"vega\": \"https://cdn.jsdelivr.net/npm/vega@6?noext\",\n",
+       "      \"vega-lib\": \"https://cdn.jsdelivr.net/npm/vega-lib?noext\",\n",
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+       "      var key = `${lib.replace(\"-\", \"\")}_version`;\n",
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+       "        .then(() => displayChart(vegaEmbed));\n",
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+       "</script>"
+      ],
+      "text/plain": [
+       "alt.Chart(...)"
+      ]
+     },
+     "execution_count": 14,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "price_time_series = pl.DataFrame({'price':[100.0,120.0,100.0]})\n",
+    "research.plot_column(price_time_series, 'price')"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "497659ef",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div><style>\n",
+       ".dataframe > thead > tr,\n",
+       ".dataframe > tbody > tr {\n",
+       "  text-align: right;\n",
+       "  white-space: pre-wrap;\n",
+       "}\n",
+       "</style>\n",
+       "<small>shape: (3, 5)</small><table border=\"1\" class=\"dataframe\"><thead><tr><th>price</th><th>delta</th><th>return</th><th>log_return</th><th>test</th></tr><tr><td>f64</td><td>f64</td><td>f64</td><td>f64</td><td>f64</td></tr></thead><tbody><tr><td>100.0</td><td>null</td><td>null</td><td>null</td><td>null</td></tr><tr><td>120.0</td><td>20.0</td><td>0.2</td><td>0.182322</td><td>100.0</td></tr><tr><td>100.0</td><td>-20.0</td><td>-0.166667</td><td>-0.182322</td><td>120.0</td></tr></tbody></table></div>"
+      ],
+      "text/plain": [
+       "shape: (3, 5)\n",
+       "┌───────┬───────┬───────────┬────────────┬───────┐\n",
+       "│ price ┆ delta ┆ return    ┆ log_return ┆ test  │\n",
+       "│ ---   ┆ ---   ┆ ---       ┆ ---        ┆ ---   │\n",
+       "│ f64   ┆ f64   ┆ f64       ┆ f64        ┆ f64   │\n",
+       "╞═══════╪═══════╪═══════════╪════════════╪═══════╡\n",
+       "│ 100.0 ┆ null  ┆ null      ┆ null       ┆ null  │\n",
+       "│ 120.0 ┆ 20.0  ┆ 0.2       ┆ 0.182322   ┆ 100.0 │\n",
+       "│ 100.0 ┆ -20.0 ┆ -0.166667 ┆ -0.182322  ┆ 120.0 │\n",
+       "└───────┴───────┴───────────┴────────────┴───────┘"
+      ]
+     },
+     "execution_count": 23,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "price_time_series.with_columns(\n",
+    "    pl.col('price').diff().alias('delta'),\n",
+    "    ((pl.col('price')-pl.col('price').shift())/pl.col('price').shift()).alias('return'),\n",
+    "    (pl.col('price')/pl.col('price').shift()).log().alias('log_return'),\n",
+    ")"
+   ]
   }
  ],
  "metadata": {