A body is projected from the earth at angle $30^{\circ}$ with the horizontal with some initial velocity. If its range is 20 m, the maximum height reached by it is : (in meters)

Question

$$\begin {array} {1 1} (a)\;5 \sqrt 3 & \quad (b)\;\frac{5}{\sqrt 3} \\ (c)\;\frac{10}{\sqrt 3} & \quad (d)\;10 \sqrt 3 \end {array}$$