$(5$ pts$)17.$ A quantity of $0\mathrm{.}400$ moles of monatomic ideal gas $)=3\frac{R}{2},C_p=(5\frac{R}{2}$ undergoes an expansion at constant pressure. The initial temperature of the gas is $80\mathrm{.}0$ K and the final temperature is $130\mathrm{.}0$ K $.$ In this process what is the change in the internal energy of the gas?

$($a$)$ zero

$($b$)155$ J

$($c$)249$ J

$($d$)416$ J

$($e$)$ none of the above answers