Answer
$64kg$
Work Step by Step
First, calculate the volume of the room in cubic feet:
$V=14.5 ft*16.5 ft*8 ft=1914 ft^3$
Now, the rest of this problem can be solved using dimensional analysis. After using the standard conversion from cubic feet into liters, the units of $ft^3$ cancel out, leaving the answer in liters.
$(1914 ft^3)*(28.317 L/ft^3)=5.4198738*10^4 L$
Then, using the density of air in grams per liter, the units cancel, leaving the answer in grams.
$(5.4198738*10^4 L)*(1.19 g/ L)=6.4496498*10^4 g \approx 64kg$
