**1**

Two ships are sailing in the sea on the two sides of a lighthouse. The angle of elevation of the top of the lighthouse is observed from the ships are 30º and 45º respectively. If the lighthouse is 100 m high, the distance between the two ships is:

**2**

The angle of elevation of a ladder leaning against a wall is 60º and the foot of the ladder is 4.6 m away from the wall. The length of the ladder is:

**3**

An observer 1.6 m tall is \(20\sqrt3\) away from a tower. The angle of elevation from his eye to the top of the tower is \(30^{\circ}\). The heights of the tower is:

**4**

From a point P on a level ground, the angle of elevation of the top tower is 30º. If the tower is 100 m high, the distance of point P from the foot of the tower is:

**5**

The angle of elevation of the sun, when the length of the shadow of a tree √3 times the height of the tree, is: