Answer
See answers.
Work Step by Step
$\Delta U$ is proportional to the change in temperature. It is greatest for the isobaric process, is zero for the isothermal process, and is least (because it is negative) for the adiabatic process.
The work done is the area under the P-V curve. It is greatest for the isobaric process, intermediate for the isothermal process, and is the least for the adiabatic process.
From the first law of thermodynamics, $Q=\Delta U+W$. It is zero for the adiabatic process (by definition of an adiabatic process) and from the earlier discussion in this problem, it is maximum for the isobaric process.
