129 meter from the foot of a cliff on level of ground, the angle of elevation of the top of cliff is 30 °. The height of this cliff is 

A ladder 20 m long is leaning against a vertical wall. It makes an angle of 30° with the ground. How high on the wall does the ladder reach?

The top of two poles of height 24 m and 42 m are connected by a wire. If the wire makes an angle of 60° with the horizontal, then the length of the wire is

The angle of elevation of the foot of a house from the top of a tower is twice the angle made with the top of this house. If the height of the tower is 75 meters. And the elevation angle of the foot of the house from the top of the tower is 60 degrees. So what is the height of the house?

If the angle of the elevation of sun is θ and the length of the shadow of a pole of length P is S, then 

From the top of a lamp post of height x metres, two objects on the ground on the same side of it (and in line with the foot of the lamp post) are observed at angles of depression of 30° and 60°, respectively. The distance between the object is $$ {32{\sqrt{3}{\ meter}}}$$. The value of  x is:

A ladder rests against a wall at a height of 10 meters. If the ladder makes 30° along the ground. Find the distance from the wall of the foot of the ladder.

The angle of elevation of the top of a tower from a point A on the ground is 30^o. On moving a distance of 20 m towards the foot of the tower to a point B, the angle of elevation increase to 60^o.The height of the tower is-