Final answer:
The slope of the height over time for the roller coaster is 4/3, and the maximum height reached after 54 seconds is 72 meters.
Step-by-step explanation:
The slope of the line representing the height of the car in terms of time is calculated by the change in height over the change in time. For this roller coaster car, it gains 4 meters in height every 3 seconds, so the slope is 4 meters/3 seconds or 4/3.
To determine the maximum height after 54 seconds, we multiply the rate of ascent by time. The car ascends 4 meters every 3 seconds, so in 54 seconds it will ascend 54/3 = 18 times 4 meters, giving us 72 meters as the maximum height.