A river is flowing from east to west at a speed of $5\, m/min$ A man on south bank of river, capable of swimming $10\,m/min$ in still water, wants to swim across the river in shortest time. He should swim
A river is flowing from east to west at a speed of $5\, m/min$ A man on south bank of river, capable of swimming $10\,m/min$ in still water, wants to swim across the river in shortest time. He should swim
- A
Due north
- B
Due north-east
- C
Due north-east with double the speed of river
- D
None of these
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