4. A video camera is mounted on top of the shorter of two buildings. The angle of depression from the camera to the base of another building is 31. The angle of elevation from the camera to the top of the taller building is 25. (Shown in diagram below). a) How tall is the smaller building? Round your answer to the nearest metre. 25; 31 [3 marks] 31 m b) How tall is the taller building? Round your answer to the nearest metre. [3 marks]