Sun...related rates question..help me out please?

On a morning of a day when the sun will p directly overhead, the shadow of an 80 ft building on level ground is 60 ft long as shown in the figure. at the moment in question the angle theta the sun makes with the ground is increasing at the rate of .27 degrees/min. at what rate is the shadow length decreasing? express your answer in in/min to the nearest tenth. remember to use radians.