What density is expressed by a gas that has a mass of 42*kg, and occupies a volume of 22*m^3?

$\frac{42}{22} \cdot k g \cdot {m}^{-} 3$.
$\text{Density, } \rho$ $=$ $\text{Mass"/"Volume}$ $=$ $\frac{42 \cdot k g}{22 \cdot {m}^{3}}$ $\cong$ $1.91 \cdot k g \cdot {m}^{-} 3$