Answer:
The 1st, 2nd, and 3rd are correct.
Explanation:
The dimensions are in fact 3*2*2 1/2. If you count it up, that is correct.
The volume is 15 cubic inches. The answer to 3*2*2 1/2 is 15.
The third is given. If you double the size of each unit, you double the size of the prism.
Hope that this helps!