1. The problem statement, all variables and given/known data An ideal gas with Cv = 5 2R, and γ = 1.4 starts at a volume of 1.5m3 , a pressure of 2.0×105Pa ,and a temperature of 300K. It undergoes an isobaric expansion until the volume is V , then undergoes an adiabatic expansion until the volume is 6.0m3 , and finally undergoes an isothermal contraction until it reaches the original state. 2. Relevant equations What is the efficiency of this heat engine? 3. The attempt at a solution I am aware that the answer is 0.19, and that efficiency is ∆W/∆Qh but I am unsure of how to find ∆W and ∆Qh in this scenario.