Given:

EVO: BDC

EVC: TDC

IVO: $,0\mathrm{.}05L$ After TDC $($late$)$

IVC: BDC

Energy Release: $,0\mathrm{.}05L$ Before TDC $($early$)$

k$\_$combustion$=1\mathrm{.}38$

k$\_$expansion$=1\mathrm{.}35$

k$\_$intake$=1\mathrm{.}4$

${}_C=1$

$($a$)$ Find the thermal efficiency of the engine ${}_t(70$ points$)$

$($b$)$ Draw the P$-$V diagram for the engine $(30$ points$)$