fix links

Author: TomNicholas

intermediate/datastructures-intermediate.ipynb

@@ -30,7 +30,7 @@
     "\n",
     "Variables hold arbitrary metadata, dimension names, and an Array of data\n",
     "\n",
-    "![image.png](../_static/variable.png)\n",
+    "![image.png](../_static/variable-model.png)\n",
     "\n",
     "## DataArray\n",
     "\n",
@@ -585,7 +585,7 @@
     "## Other field DataStructures\n",
     "\n",
     "\n",
-    "Link to next notebook: [Data structures In Biology](../../intermediate/BiologyDataset.ipynb)"
+    "Link to next notebook: [Data structures In Biology](./BiologyDataset.ipynb)"
    ]
   },
   {
@@ -624,6 +624,16 @@
     "For more see the [user guide](https://docs.xarray.dev/en/stable/plotting.html), the [gallery](https://docs.xarray.dev/en/stable/examples/visualization_gallery.html), and [the tutorial material](https://tutorial.xarray.dev/fundamentals/04.0_plotting.html)."
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": []
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": []
+  },
   {
    "cell_type": "code",
    "execution_count": null,