A moving beltway at an airport has a speed v1 and a length L. A woman stands on the beltway as it moves from one end to the other, while a man in a hurry to reach his flight walks on the beltway with a speed of v2 relative to the moving beltway.

(a) What time interval is required for the woman to travel the distance L? (Use any variable or symbol stated above as necessary.)

(b) What time interval is required for the man to travel this distance? (Use any variable or symbol stated above as necessary.)

(c) A second beltway is located next to the first one. It is identical to the first one but moves in the opposite direction at speed v1. Just as the man steps onto the beginning of the beltway and begins to walk at speed v2 relative to his beltway, a child steps on the other end of the adjacent beltway. The child stands at rest relative to this second beltway. How long after stepping on the beltway does the man pass the child? (Use any variable or symbol stated above as necessary.)