
$\therefore \,dQ = n{C_p}dT;\,where\,{C_p}\,is\,specific\,heat\,at\,constant\,pressure.$
or $dQ = n\left( {\frac{5}{2}R} \right)dT$
$Also,\,dW = PdV = nRdT\,\left( {PV = nRT} \right)$
Required ratio$ = \frac{{dW}}{{dQ}} = \frac{{nRdT}}{{n\left( {\frac{5}{2}R} \right)dT}} = \frac{2}{5}$

Statement $1$ : Ratio of volumes $\frac{{{V_E}}}{{{V_F}}} = 4$
Statement $2$ : Magnitude of work done in isothermal compression $EF$ is $2RT_3\ ln\ (2)$
Statement $3$ : Ratio of heat supplied to gas in the process $AB$ to heat rejected by gas in process $EF$ is $\frac{{{T_1}}}{{2{T_3}}}$
Statement $4$ : Net work done by gas in the cycle $ABCDEFA$ is $(T_1 + T_2 - 2T_3) R\ ln\ (2)$
Find the number of correct statement $(s)$ given for the cyclic process followed by gas