2. [2/4 Points] I DETAILS II PREVIOUSANSWERS I OSCOLPHYSZO167.1.P.OO4. I MYNOTES I ASKYOURTEACHER II PRACTICEANOTHER I Suppose a car travels 108 km at a speed of 30.0 m/s, and uses 1.80 gallons of gasoline. Only 30% of the gasoline goes into useful work by the force that keeps the car moving at constant speed despite friction. (The energy content of gasoline is 1.30 x 108 J per gallon.) (a) What is the force (in N) exerted to keep the car moving at constant speed? 752.4 x N (b) If the required force is directly proportional to speed, how many gallons will be used to drive 108 km at a speed of 28.0 m/s? , gallons Additional Materials L3 Reading