The basic relationship between mass m, volume V and density d is given by [tex]d= \frac{m}{V} [/tex] re-arranging the equations and using m=1 kg and [tex]d=0.0013 g/mL = 0.0013 kg/L[/tex], we find the volume: [tex]V= \frac{m}{d}= \frac{1 kg}{0.0013 kg/L}=769.2 L [/tex] and since [tex]1 L = 1 m^3[/tex], this corresponds to [tex]769.2 m^3[/tex] of air.