3. A boy wishes to row across a river in the shortest possible time. He can row at 2 m/s in still water and the river is flowing at 1 m/s. At what angle with respect to the water velocity should he point the bow (the front of the boat)?
(A) 30°
(B) 45°
(C) 60°
(D) 90°
(E) none of the above.

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