The amount of a pollutant (measured as parts per million) in a local lake can be modeled by the function of A (t) = 14(2.71)^-016-4, where t is the
number of years since a government program was began to help clean up
the lake. About how long will it take for the amount of pollutant to reach 7
parts per million?

O 7.85 years
O 43.45 years
O 83.51 years
O 12.52 years