1. The problem statement, all variables and given/known data A water tank has the shape of an inverted circular cone with a base diameter of 8m and a height of 12m. a) If the tank is being filled with water at the rate of 5m^3/min, at what rate is the water level increasing when the water is 5m deep? b) If the tank is full of water and being drained at the rate of 7m^3/min, at what rate is the water level decreasing when the water is 7m deep? 2. Relevant equations 3. The attempt at a solution a) V'(t) = 5 r = (1/3)h V = (1/3)(pi)((1/3h)^2)h =(1/27)(pi)(h^3) V' = (1/9)(pi)(h^2)h' sub in known values~ 5 = (1/9)(pi)(144)h' h' = 5 / (50.24) =.09 I have a feeling I have to sub in the "water is 5m deep" part somewhere, but I don't know where. b) Same problem as above, basically.