Each of three closed $($gas$-$tight$)$ systems at $25C$ contains $1\mathrm{.}0L$ of a $10mo\frac{l}{L}$ chloroform solution, but they in equilibrium with different gas phases. System I contains $1\mathrm{.}0L$ of gas with $P_{\text{t}\text{o}\text{t}}=1\mathrm{.}0$atm, System II contains $2\mathrm{.}0L$ of gas with $P_{\text{t}\text{o}\text{t}}=1\mathrm{.}0$atm, and System III contains $1\mathrm{.}0L$ of gas with $P_{\text{t}\text{o}\text{t}}=2\mathrm{.}0$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?