Answer:
The answer for 16 is A, the answer for 20 is D, and the answer for 25 is A
Explanation:
For 16, the equation is 6a = 72. 6a is also equal to 6*a. To get a one side by itself, you have to divide both sides by 6.
For 20, it only makes sense for it to be a triangular prism because it has 2 triangles as the base and 3 faces
For 25, you can subtract what was the leftovers from the total number of pizzas. 8 - 1 3/4 - 5/6 is about 5.41, which is closer to 5 so the answer is 5.