Question

at 2 p.m.,the level of the water in the pool was 10 feet.at 6 p.m., the level of water was 2 feet.find the rate of change of the water

Answer 1

2 pm to 6 pm = 4 hrs
10 ft to 2 ft = -8ft
-8 ft/4 hrs 
-2 ft/hr = answer