Think about skin cells. Skin cells shed every day, if cell division didn't take place, you would just constantly be losing skin cells.
You're on K12 haha :0
I think it's the second answer choice but not sure. Sorry if I'm wrong
<span>Model construction.....</span>
the predominant pollutants include nitrogen oxides, particularly nitric oxide (NO) and nitrogen dioxide (NO2), and volatile organic compounds.
