A first-order homogeneous liquid-phase reaction ($A \rightarrow B$) occurs in an adiabatic, ideal mixed flow reactor operating at steady state. The volumetric flow rate of the feed is $4 \text{ L min}^{-1}$ and volume of the reactor is $20 \text{ L}$. At the reactor temperature of $500 \text{ K}$, the reaction rate constant is $1 \text{ min}^{-1}$, and heat of reaction is $-20 \text{ kcal mol}^{-1}$. The average heat capacity of the feed as well as the reaction mixture in the temperature range of interest is $0.3 \text{ kcal mol}^{-1}\text{ K}^{-1}$. At the inlet, the feed temperature (in K) is _________ (rounded off to one decimal place).