P and Q are two towns. A man drives from P to Q at an average speed of 50 km/h. He stops at Q for 4 hours and then heads back to P at an average speed of 40 km/h following the same route. What is his average speed (in km/h correct to two decimal places) if he takes 22 hours for the entire trip?

A

42.42

B

36.36

C

48.48

D

45.00