First lets get the formula for a triangular prism

First lets plug in our numbers

It really doesnt matter how you multiply everything, but you end up with 119cubic feet.
If a number has a decimal that is .5+, you round up. If it is .4-, you round down. So 817.502 would be 818.
It's B.) The student’s answer is not reasonable. Estimation: 170 + 90 = 260
Answer:
the sum of 4 and a number
4 plus a number