please show all work!

3. John and Jack are out on the lagoon riding in a speed boat when their engine stalls. Samuel and Abigail come to the rescue and throw them a rope and then begin pulling them to the dock at 4ft/sec. a) If John and Jack are 8 feet higher than the boat, how fast is the boat approaching the dock when 13 feet of rope is out? b) At what rate is the angle changing at the top of the rope at this same time