A aeroplane is flying horizontally with speed of 432 km/hr at height h meter from ground. Its angle of elevation from a point on ground is 60°. After 20 sec its angle of elevation from same point is 30° then the height 'h' is equal to

(1) $1200\sqrt3$

(2) $600\sqrt3$

(3) $1800\sqrt3$

(4) $1000\sqrt3$

(1) $1200\sqrt3$

(2) $600\sqrt3$

(3) $1800\sqrt3$

(4) $1000\sqrt3$