A rigid insulated tank containing an ideal gas at $300$ K and $1$ bar is being filled from an external pressurized line supplying the same gas at $300$ K and $10$ bar. When the mass of gas inside the tank has doubled, its temperature (in K ) is _________ $\text{(rounded off to the nearest integer)}$.
Assume ratio of specific heats to be constant for this process and equal to $1.4$.
