An observer on the top of a mountain, 500 m above the sea level, observes the angles of depression of the two boats in his same place vision to be 45 ° and 30 ° respectively. Then the distance between the boats, if the boats are on the same side of the mountain, is 

The angle of elevation of the top of two vertical towers as seen from the middle point of the line joining the foot of the towers are 60° and 30°, respectively. The ratio of the heights of the tower is

If the length of a shadow of a pole on a level ground is twice the length of that pole, the angle of elevation of the sun is:-

From a tower 125 metres high the angle of depression of two objects, which are horizontal line through the base of the tower are 45° and 30° and they are on the same side of the tower. The distance (in metres) between the objects is

A man standing on the bank of river observes that the angle subtended by a tree on the opposite bank is 60°. When he retrieves 36 m from the bank, he find that the angle is 30°. The breadth of the river is

The angle of elevation of a tower from a distance 50 m from its foot is 30°. The height of the tower is 

The angles of elevation of the top of a temple, from the foot and the top of a building 48 m high, are 60^o and 30^o respectively. The height of the temple is more than the building. The height of the temple is-

A pilot in an aeroplane at an altitude of 200 m observes two points lying on either side of a river. If the angles of depression of the two points be 45 ° and 60 °, then the width of the river is