**Question:**A boat can travel with a speed of 13 km/hr in still water. If the speed of the stream is 4 km/hr, find the time taken by the boat to go 68 km downstream.

**Options are:**

A. 2 hours

B. 3 hours

C. 4 hours

D. 5 hours

**Correct answer is:**

C. 4 hours

C. 4 hours