The above p-v diagram represents the thermodynamic cycle of an engine, operating with an ideal monoatomic gas. The amount of heat, extracted from the source in a single cycle is

Explanation

`P_(0)V_(0)=nRT_(A), 2P_(0)V_(0nRT_(B), 2P_(0)2V_(0)=nRT_(C)`
Heat supplied `H=nC_(v)DeltaT_(AB)+nC_(v)DeltaT_(BC)`
`=nC_(v)=((2P_(0)V_(0))/(nR)-(P_(0)V_(0))/(nR))+nC_(P)((4P_(0)V_(0))/(nR)-(2P_(0)V_(0))/(nR))`
`=n((3)/(2)R)((P_(0)V_(0))/(nR))+n(5)/(2)R((2P_(0)V_(0))/(nR))=(12)/(2)P_(0)V_(0)`