On a sunny and cold morning , the sun will pass directly overhead of an 80 ft building. At noon( before the sun passes directly over the building) ,the sun casts a 60 ft shadow on level ground and the angle the sun makes with the grund, A, is increasing at the rate of 0.27 degrees per minute.

At noon

a) At what rate is the shadow decreasing?

b)How fast is the distance from the top of the building to the end of the shadow changing ( it's getting shorter)

I know I'm given a rate , which is dA/dt = 0.27 degrees / minute ; however, my instructor only covered related rates briefly .Can someone help me with this problem? thanks in advance