Part A: How much higher is checkpoint 2 than checkpoint 5?
Get the difference between the two checkpoint, and we get
Therefore, checkpoint 2 is higher than checkpoint 5 by 1593 feet.
Part B: Altitude of the top hill.
Since checkpoint 5 is -185 feet above sea level, if the top of the hill is 570 feet above then
Therefore, the top of the hill is 385 feet above sea level.