From the top of hill 240 m high, the angles the angles of depression of the top and bottom of a pole are 30° and 60°, respectively. The difference (in m) between the height of the pole and its distance from the hill is:

Answer: Option D

Solution

Answer: Option D

Solution:

$$\begin{array}{rl}& 3\to 240\\ & \sqrt{3}\to \frac{240}{3}\times \sqrt{3}=80\sqrt{3}\\ & \text{Height of the pole}\\ & =160-80\sqrt{3}\\ & =80\left(2-\sqrt{3}\right)\end{array}$$