A gas absorbs $100 \mathrm{~J}$ of heat and is simultaneously compressed by a constant external pressure of $1.5 \mathrm{~atm}$ from a volume of $8.0 \mathrm{~L}$ to $2.0 \mathrm{~L}$. The change in internal energy for the gas in Joules is $(1 \mathrm{~L}-\mathrm{atm}=101.32 \mathrm{~J})$