If a wooden block is placed against a 15 meter tree such that it just reaches the top of the tree, with the angle of elevation of the tree is 30°, then find the length of the wooden block?

A man standing on the bank of a river observes that the angle subtended by a tree standing on the opposite bank is 60 degrees on his side of bank. When he moved away 24m from the bank, he finds the angle to be 30 degrees. Find the breadth of the river:

From A point on a bridge across a river, the angles of depression of the banks on opposite sides of the river are 30° and 45°, respectively. If the bridge is at a height of 9 m from the surface of the river, then find the width of the river.

From a point 60 m away from the foot of a building, the angle of elevation of the top of the building is 30°. What is the height of the building?

The tops of two poles of height 38 m and 56 m are connected by a cable. If the cable makes an angle of 30° with the horizontal, then the distance between the bases of the poles is:

In a $\Delta ABC$ right angled at A, if $\angle ABC = 60^\circ$ and AC = 4 units, then length of BC (in units) is :

The cliff of a mountain is 180 m high, and the angles of depression of two ships on the same side of cliff are 30° and 60°. Find the distance between the two ships in meter.