Answer
$Q=79.6\ kJ$ (in)
Work Step by Step
From the energy balance:
$Q-W_b=\Delta U=0$ (isothermal)
$Q=W_b=mRT\ln\left(\frac{P_1}{P_2}\right)$ (boundary work for isothermal processes)
Given $m=1\ kg,\ R=0.287\ kJ/kg.K,\ T=127°C,\ P_1=200\ kPa,\ P_2=100\ kPa$
$Q=79.6\ kJ$ (in)
