# Ques. -23

**Calculus**Level 4

An inverted conical tank of radius \(2m\) and height \(4m\) is initially full of water has an outlet at bottom. The outlet is opened at some instant. The rate of flow through the outlet at time \(t\) is \((6 \cdot h^{\frac{3}{2}})\), where \(h\) is the height of water level above the outlet at time \(t\). then the time it takes to empty the tank is :