The vertices of a rectangle are plotted on the coordinate grid shown. A graph with the both the x and y-axes numbered starting from negative 8 with units of one up to 8. There are points plotted at negative 4, 4, at 5, 4, at negative 4, negative 4, and at 5, negative 4. What is the area of the rectangle shown? 32 square units 36 square units 64 square units 72 square units