Fix typo in #204

Author: davidmascharka

docs/Module3_IntroducingNumpy/BasicArrayAttributes.ipynb

@@ -73,7 +73,7 @@
     "\n",
     "**ndarray.dtype**:\n",
     "\n",
-    "An object describing the data type of the elements in the array. Recall that NumPy's ND-arrays are *homogeneous*: they can only posses numbers of a uniform data type. \n",
+    "An object describing the data type of the elements in the array. Recall that NumPy's ND-arrays are *homogeneous*: they can only possess numbers of a uniform data type. \n",
     "\n",
     "```python\n",
     "# `example_array` contains integers, each of which are stored using 32 bits of memory\n",