The ratio of the speed of a motorboat to that of the current of water is 31 : 6. The motorboat starts from a point and covers a certain distance along the current in 4 h 10 min. Find the time taken by the motorboat to come back to its initial point.

A

4 h 10 min

B

5 h 10 min

C

5 h 50 min

D

6 h 10 min