It is 784 cubic inches so you are right
If it was physics or math try to solve all problems you have and try to search for more questions to solve the more you solve the more you will gain marks ,if it was a subject that needs to memorize write down the things you forget on nots and read them in the morning .. do not forget to take a break whenever you lose your passion just believe in yourself you can do it
Answer and Explanation: The answer is in the 1st image, and the explanation is in the 2nd image.