What percent of species become extinct when mass extinction occurs?

Scientists estimate that at least 99.9 percent of all species of plants and animals that ever lived are now extinct.

Explanation:

(Happy to help)

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.