Read and understand the problem, then solve. Stating what is asked in the problem. During the Apollo 14 mission, Alan Shepard hit a golf ball on the Moon. The function h(t)=18t-0.8t² models the height of the golf ball's trajectory on the Moon, where h(t) is the height, in metres, of the ball above the surface of the Moon and t is the time in seconds. Determine the instantaneous rate of change in the height of the ball at 5 seconds.