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A man of mass 80 kg carrying a load of 2...

A man of mass 80 kg carrying a load of 20 kg walks up a stair case in 20s. If the number of steps is 40 and which and height of each step are 20 cm and 15 cm respectively. The efficiency of the man is

A

0.2

B

0.25

C

0.4

D

0.5

Text Solution

Verified by Experts

The correct Answer is:
B
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