TS EAMCET Medical 28 Sept 2020 Shift 2 Paper

Two cylinders A and B of equal capacity are connected to each other via a stopcock. A contains an ideal gas at standard temperature ( T1 )and pressure. B is empty. Then the entire system is thermally insulated. The stopcock is suddenly opened. After the as reaches equilibrium the temperature (T2) of the gas measured. Which of the following is correct?