Mr_green... do u go to scn high?
This one has got me stumped too =[
The base of a cone-shaped tank is a circle of radius 5 feet, and the vertex of the cone is 12 below the base. The tank is filled to a depth of 7 feet, and water is flowing out of the tank at a rate of 3 cubic feet per minute.
Find the rate of change of the depth of the water in the tank.