41. Exemplar exercise problems XVI

The lower window of a house is at a height of $2 \ m$ above the ground and its upper window is $4 \ m$ vertically above the lower window. At certain instant the angles of elevation of a balloon from these windows are observed to be $60^{\circ}$ and $30^{\circ}$, respectively. Find the height of the balloon above the ground.

 

 

The height of the balloon $=$ $m$