A hemispherical tank of radius 2 meters is initially full of water and has an outlet of 12cm2 cross section area at the bottom. The outlet is opened at some instant. The flow through the outlet is according to the law
where g(t) and h(t) are respectively the velocity of the flow through the outlet and the height of the water level above the outlet at the time t, and g is the acceleration due to gravity. Find the time it takes to empty the tank. (Hint: Form a differential equation by relating the decrease of water level to the outflow).
a) 
b) 
c) 
d) 