An ideal gas $Cp=(\frac{7}{2})R$ and $Cv=(\frac{5}{2})R,$ undergoes a cycle consisting of the following

mechanically reversible steps:

a$)$ An adiabatic compression from $P_1,V_1,T_1$ to $P_2,V_2,T_2$

b$)$ An isobaric expansion from $P_2,V_2,T_2$ to $P_3=P_2,V_3,T_3$

c$)$ An adiabatic expansion from $P_3,V_3,T_3$ to $P_4,V_4,T_4$

d$)$ A constant$-$volume process from $P_4,V_4,T_4$ to $P_1,V_1=V_4,T_1$

Sketch this cycle on a $PV$ diagram and determine its thermal efficiency if $T_1=200C,$

$T_2=500C,T_3=1,700C,$ and $T_4=700C.$

$($Ans$.$ This is the same cycle as illustrated in Fig $8\mathrm{.}10$

of SVA; efficiency is $0\mathrm{.}591)$

show all steps please