Prob. $1\mathrm{.}5\mathrm{.}4$ p$.$ IP$-3[$Ans: $0\mathrm{.}00458$ slugs $\frac{?}{f{t}^3}].$

$1\mathrm{.}5\mathrm{.}4$ WP A closed tank having a volume of $2f{t}^3$ is filled with $0\mathrm{.}30lb$ of a gas. A pressure gage attached to the tank reads $12$ psi when the gas temperature is $80F.$ There is some question as to whether the gas in the tank is oxygen or helium. Which do you think it is$?$ Explain how you arrived at your answer.