Answer: The second option.
Step-by-step explanation:
1. Calculate the first volume assuming that the figure is completed (with no missing part). Therefore, you must apply the formula for calculate the volume of a square prism:

Where s is the side of the base and h is the height.
2. Then:

4. The volume of the missing part is calculated with the formula of a rectangular prism:

Where l is the lenght, w is the width and h is the height. Then:

5. Therefore, you must subtract both volumes to obtained the volume of the figure:

Answer:
A
Step-by-step explanation:
The easiest way to figure this out is to substitute in the variables. So for a, 2=-5+7 is correct, and 7=0+7 is correct as well. If you were to look at the other answers, you would see that the equation would not match up. Hope this helps!