$($a$)$

What is the efficiency $($in percent$)$ of a cyclical heat engine in which $25\mathrm{.}0$ kJ of heat transfer occurs to the environment for every $80\mathrm{.}0$ kJ of heat transfer into the engine?

$\%$

$($b$)$

How much work $($in kJ$)$ does it produce for $600$ kJ of heat transfer into the engine?

kJ