A light truck weighs 3,100lb and is rated at 30 miles per gallon for 60mph highway driving on level ground. Under those conditions, the engine must overcome air resistance, rolling resistance, and other sources of friction.
a)The coefficient of drag is 0.56 at 60mph,and the truck's frontal area is 29ft^{2}. What is the drag force on the truck (in lb)?
b) How much horsepower must the engine produce at 60mph just to overcome air resistance?hp
c) In part (b)how much gasoline (in gal) would be consumed each hour?