**Question:** Speed of a boat in standing water is 9 kmph and the speed of the stream is 1.5 kmph. A man rows to a place at a distance of 105 km and comes back to the starting point. The total time taken by him is:

**Options are:**

A. 16 hours

B. 18 hours

C. 20 hours

D. 24 hours

Correct answer is:

D. 24 hours