A well insulated rigid container of volume $1 \: m^3$ contains $1.0 \: kg$ of an ideal gas $[C_p = 1000 \: J/(kg\cdot K)$ and $C_v=800 J/(kg \cdot K)]$ at a pressure of $105 \: Pa$. A stirrer is rotated at constant rpm in the container for $1000$ rotations and the applied torque is $100 \: N-m$. The final temperature of the gas (in $K$) is

- $500.0$
- $773.0$
- $785.4$
- $1285.4$