A balloon behaves so the pressure is $P=C_{2} V^{1 / 3}$ $C_{2}=100 \mathrm{kPa} / \mathrm{m} .$ The balloon is blown up with air from a starting volume of $1 \mathrm{m}^{3}$ to a volume of $3 \mathrm{m}^{3} .$ Find the final mass of the air, assuming it is at $25^{\circ} \mathrm{C},$ and the work done by the air.