Solve the following situational problems involving the central angle. Show your solutions:
1. If the minute hand of the clock has a length of 5 in., how far does its tip travel in 22 min?
2. If a locomotive wheel with a diameter of 15 meters rolls 13 meters, how many radians does it turn?
3. A central angle in a propeller sweeps out an area of 45 square units on a circle of radius 6 units. What is the measure of the angle?