An airplane is flying east at a certain altitude of 30500 feet. When first seen to the east of the observer, the angle of elevation to the plane is 63.6 degrees. After 33 seconds the angle of elevation is 56.1 degrees. Find the speed in feet per second of the plane.

Is the answer approx 162 feet per second or 1,861.9 feet per second?

What I did was: (30500/Tan(56.1))-(30500/Tan(63.1))=162 feet/sec

Is this correct