Suppose your car averages 32 miles per gallon on the highway if your average speed is 60 miles per hour, and it averages 25 miles per gallon on the highway if your average speed is 75 miles per hour.
(a) What is the driving time for a 1500-mile trip if you drive at an average speed of 60 miles per hour? (Give your answer in exact number of hours.)
(b) What is the driving time for a 1500-mile trip if you drive at an average speed of 75 miles per hour? (Give your answer in exact number of hours.)
(c) Assume a gasoline price of $2.25 per gallon. What is the gasoline cost for a 1500-mile trip if you drive at an average speed of 60 miles per hour? (Round your answer to the nearest cent.)