A gas is compressed in a cylinder by a movable piston to a volume onehalf its original volume. During the process 300 kJ heat left the gas and internal energy remained same. The work done on gas in Nm will be  (a) 300 Nm  (b) 300,000 Nm  (c) 30 Nm  (d) 3000 Nm  (e) 30,000 Nm.

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Answer : b

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