Q$1.0\mathrm{.}5kg$ of methane $(C{H}_4)$ is in a box at $20C$ and $\frac{4}{b}ar.$ The cylinder is heated in an isometric process until the absolute temperature has doubled. How much heat has come into the system?

Answer: $319\mathrm{.}8kJ$ Hint: Use average $c_p$ value, but remember $c_p$ is across a constant pressure.