Why wouldn’t the water cycle constantly adds pollution to the air be important in the water cycle

This wouldn't be important because the water cycle is simply a series of events that occur starting from Evaporation, condensation, sublimation, precipitation, transpiration, run off, and lastly infiltration. Though you may think that through a certain step the water is adding pollution to the air, this is not something that is being examined or asked of you to identify when specifically dealing with the water cycle alone. Hope that answers your question.

9.9 years

a = p(1 + rt) . . account balance after time t at rate r starting with principal p

3000 = 2500(1 + 0.0202t) . . filling in the given numbers

1.2 = 1 + 0.0202t . . divide by 2500

0.2 = 0.0202t . . . subtract 1

0.2/0.0202 = t ≈ 9.901

it will take about 9.9 years for the account balance to reach $3000.

multiple allele inheritance is traits controlled by more than 2 alleles (ex: pigeons having 3 alleles of one gene govern their feather color).   so the answer is a.