For these kinds of problems, focus on getting one unit, and then do the other one.
Since there are 60 seconds in a minute, 39 feet per minute=39/60 or 13/20 feet per second.
Since there are 3 feet in a yard, 13/20 feet per second =13/60 yards per second.
The answer is 13/60 yards per second.
Hope this helps!
