Tank A (1 m^{3}) contains air at 10 °C and 350 kPa. It is connected through a valve to tank B, which contains 3 kg of air at 35 °C and 150 kPa. The valve is opened and the whole system comes to thermal equilibrium with the surroundings at 20 °C. Determine (a) the volume of tank B (in m^{3}) and (b) the final equilibrium pressure of the air (in kPa). Take R = 0.287 kJ/kg·K.