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A boat taken two hours to travel 8 km an...

A boat taken two hours to travel 8 km and back in still water lake. If the velocity of water is 4km/h,what is the time taken for going up stream of 8 km and coming back ?

A

2 hours

B

2 hours 40 mint

C

1 hr 20 mins

D

cannot be estimated.

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Verified by Experts

The correct Answer is:
B
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