Five hundred flies of one species were sprayed with a new insecticide. twenty-four hours later, nearly all the flies were dead. however, a few survived. which principle best explains why some flies survived?

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.

i think that c)gold was found there

but i am not sure