Okay, nevermind, I solved that one too (for being the "Urgent Homework Help" forum, ya'll are kinda slow on the draw). Here's one thet's really giving me some trouble.
A hot air balloon rising vertically is tracked by an observer located 5 miles from the lift-off point. At a certain moment, the between the observer's line-of-sight and the horizontal is [π/6] , and it is changing at a rate of 0.1 rad/min. How fast is the balloon rising at this moment?