A boy standing at one bank of river sees the top of a tree on the other bank directly opposite to the boy at an elevation of `60^@`. Stepping 40 metres back, he sees the top at an elevation of `30^@`.
Draw a rough figure and find the height of the tree.

A TV tower stands vertically on a bank of a canal. From a point on the other bank directly opposite the tower, the angle of elevation of the top of the tower is 60^(@) . From another point 20 m away from this point on the line joining this point to the foot of the tower, the angle of elevation of the top of the tower is 30^(@) (see figure below). find the height of the tower and the width of the canal. .

A TV tower stands vertically on a bank of a canal. From a point on the other bank directly opposite the tower, the angle of elevation of the top of the tower is 60^(@) . From another point 20m away from this point on the line joining this point to the foot of the tower, the angle of elevation of the top of the tower is 30^(@) (see Figure ). Find the height of the tower and the width of the canal.

Two poles of equal heights are standing opposite each other on either side of the road, which is 80m wide. From a point between them on the road, the angles of elevation of the top of the poles are 60^(@) and 30^(@) , respectively . Find the height of the poles and the distances of the point from the poles.

Two poles of equal height are standing opposite to each other on the either side of the road which is 80 m wide. From a point P between them on road, the angle of elevation of the top of a pole is 60^(@) and the angle of depression from the top of another pole at point P is 30^(@) . Find the heights of the poles and distances of the point P from the poles.

Two persons are 'a' metres apart and the height of one is double that of the other. If, from the middle point of the line joining their feet, an observer finds the angular elevation of their tops to be complementary, the height of the shorter person in metre is _______ .