What is the gas-phase concentration in each system

Each of three closed (gas-tight) systems at 25°C contains 1.0 L of a 10 µmol/L chloroformsolution but they are in equilibrium with different gas phases.System I contains 1.0 L of gas with Ptot =1.0 atm System II contains 2.0 L of gas with Ptot = 1.0 atm andSystem III contains 1.0 L of gas with Ptot= 2.0 atm.(a) What is the gas-phase concentration in each system?(b) What is the total mass that was added to (and is still in) each system?