A person standing on the bank of a river observes that the angle of elevation of the top of a tree standing on the opposite bank is `60^0dot` When he move 40 metres away from the bank, he finds the angle of elevation to be `30^0dot` Find the height of the tree and the width of the river.

Answer

Hence, the height of the building is 34.64 m and width of the river is 20 m .
(a) Wild life is a part of our environment and conservation each of its element is important for ecological balance.
(b) Ban on hunting, providing wild animals a healthy environment.