Komalb2005p2n1sk: see work below to your question.

Which of the following is the result of expanding

Nikolas calculated the volume of the prism. his work is shown below.

I'm at a bookstore with $\$35$ in my pocket and a $20\%$-off coupon. what is the cost of the most expensive book i can buy with my money and the coupon? (assume that there are books of every possible price in the bookstore. it's a large bookstore! )