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A man weighing 60 kg lifts a body of 15 ...

A man weighing 60 kg lifts a body of 15 kg to a top of building 10 m high in 30 minutes. His efficiency is :

A

0.4

B

0.3

C

0.2

D

0.1

Text Solution

Verified by Experts

The correct Answer is:
c
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