Suppose that the truck in Problem P7.8 was going up a hill with a grade of 2%. How much additional power must the engine produce to climb the hill, neglecting various frictional effects?

Data from Problem P7.8

A light truck weighs 3100 lb and is rated at 30 miles per gallon for 60-mph highway driving on level ground. Under those conditions, the engine must overcome air resistance, rolling resistance, and other sources of friction. Give your answers in the units shown.