In order that a cycle be reversible, following must be satisfied  (a) free expansion or friction resisted expansion/compression process should not be encountered  (b) when heat is being absorbed, temperature of hot source and working sub¬stance should be same  (c) when beat is being rejected, temperature of cold source and working sub-stance should be same  (d) all of the above  (e) none of the above.

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Answer :

Answer : d

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