Question

What do I do I thought it was a but my teacher said it was wrong so what do I do ?

Answer 1

Do length × width × hight

you just get 840 cf

Answer 2

The answer is c
V=1/2a•c•h
V=0.5(7)•10•12
V=3.5(10)•12
V=30(12)
V=420