Question

Whats the answer to #10. use the blue thing.

Answer 1

It is 784 cubic inches so you are right

Answer 2

You could have used 12 x 3 x 14 + 5 x 4 x 14 or
8 x 14 x 4 + 8 x 14 x 3. Write whichever one you used, then put 'but I also could have used' then write the other one.