In the given diagram of a ladder leaning against a wall, which of the following angles represents the ladder’s angle of elevation?
A point is located 18 meters away from the base of a 21-meter high house. Find the angle of elevation from the point to the top of the house.
From the top of a house 15 m tall, the angles of elevation and depression of the top and the base of a building are and respectively. Find the height of the building giving the answer to the nearest metre.