Select the correct answer. what size plywood base should you use if your post is 40 inches high? a. it must be no larger than 18 inches x 18 inches. b. it must be exactly 18 inches x 18 inches. c. it must be larger than 18 inches x 18 inches.

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! )