A man on the top of a vertical observation tower observes a car moving at a uniform speed coming directly towards it. If it takes 12 minutes for the angle of depression to change from 30° to 45°, how soon after this will the car reach the observation tower ?

A man on the top of a vertical observation tower observes a car moving

1.	A man on the top of a vertical observation tower observes a car moving at a uniform speed coming directly towards it. If it takes 12 minutes for the angle of depression to change from 30° to 45°, how soon after this will the car reach the observation tower ?
A.	4 min. 35 sec.
B.	5 min. 49 sec.
C.	6 min. 23 sec.
D.	8 min. 5 sec.
Answer» D. 8 min. 5 sec.