Let there by $n$ moles of gas.

Mass of gas $=40 n g$ or $\frac{40 n}{1000}$ or $0.04 n kg$

$\text { K.E. of gas in container }=\frac{1}{2} \times 0.04 n \times(200)^2$

$=0.02 \times n \times 4 \times 10^4$

$=8 \times 10^2 \times n J$

Now heat capacity of gas $(C)=\frac{f}{2} n R$

or $C=\frac{5}{2} R \times n$

or $C \Delta T=8 \times 10^2 \times n$

or $\frac{5}{2} \times R \times n \Delta T=8 \times 10^2 \times n$

$\Delta T=\frac{8 \times 10^2}{R} \times \frac{2}{5}$

$\Delta T=\frac{16}{5} \times 10^2=\frac{320}{R}{ }^{\circ} C$