Answer:
19.61kg
Explanation:
The first thing to do is divide the amount of feet into 3.28:
[tex]18ft*12ft*8ft=5.49m*3.66m*2.44m[/tex]
With this information, we calculate the volume:
[tex]V=5.49m*3.66m*2.44m=49.03m^{3}[/tex]
As we have the concentration and the volume, we can calculate the mass of CO:
[tex]m=400,000 \mu g/m^{3}*49.03m^{3}=19611158.4 \mu g[/tex]
As this is a very big number, we can express it in kg by dividing in 10^6:
[tex]19611158.4 \mu g/10^{6}=19.61 kg[/tex]