From the top of a building 10m high, the angle of depression of a stone lying on the horizontal ground is 69o. Calculate, correct to one decimal place, the distance of the stone from the foot of the building

A. 3.6m
B. 3.8m
C. 6.0m
D. 9.3m
E. 26.1m

Correct Answer: Option B

B. 3.8m

tan21o =x/10
x = 10 tan 21o
= 3.3839 = 3.8m