A water balloon was launched into the air from the top of a hill 38 feet above ground. The balloon's path is represented by the equation
h(t) = -162 + 48t + 38, where h(t) represents the height, in feet, and t is the time in seconds. Find the
average rate of change from the initial launch to the maximum height.

The u-drive rent-a-truck company plans to spend $13 million on 320 new vehicles. each commercial van will cost $25 comma 000, each small truck $50 comma 000, and each large truck  $80 comma 000. past experience shows that they need twice as many vans as small trucks. how many of each type of vehicle can they buy?