From the top of a 7m high building the angle of elevation of the top of a tower is 60° and the angle of depression of its foot is 45°. Find the height of the tower.

On observing from the top of a lighthouse 60 m high from the sea level, the angles of depression of two ships are 30° and 45°. If one ship is just behind the other ship on the same side of the lighthouse then find the distance between the ships.

A 1.5 m long boy is standing at a certain distance from a 30 m high building when he goes towards the high building then the angle of elevation of the top of the building from his eye becomes 60° from 30°. Find by how much distance he has walked towards the building.

From the peak of a mountain the angles of elevation of the peak from two points situated towards the east are 30° and 45°. If the distance between the points is 1 km then find the height of the mountain.

From a point A 20m high above the water level in a lake the angle of elevation of a cloud is 30°. If the angle of depression of the reflection of the cloud in the lake from point A is 60° then find the distance of the cloud from the point A.