One mole of an ideal monoatomic gas of molecular mass $$M$$ undergoes a cyclic process $$ABCA$$ shown in the figure as a density $$\rho$$ versus pressure $$P$$ curve. The correct option or options is or are

A

Work done on the gas in going from $$A$$ to $$B$$ is $$W_{AB} = \frac{MP_0}{\rho_0}\ln 2$$

B

Work done by the gas in the process $$BC$$ is $$W_{BC} = \frac{MP_0}{2\rho_0}$$

C

Efficiency $$\eta$$ of the complete cycle $$ABCA$$ is $$\eta = \frac{2}{5}\left(1 - \ln 2\right)$$

D

Heat rejected by the gas in the complete cycle $$ABCA$$ is $$Q_{ABCA} = \frac{MP_0}{\rho_0}\left(1 - \ln 2\right)$$