Solve the Problem $367 \mathrm { mg }$ Of an Isotope Is Given By

Multiple Choice

Solve the problem.
-The decay of $367 \mathrm { mg }$ of an isotope is given by $\mathrm { A } ( \mathrm { t } ) = 367 \mathrm { e } ^ { - 0.03 \mathrm { t } }$ , where $\mathrm { t }$ is time in years. Find the amount left after 57 years.

A) 356
B) 33
C) 64
D) 66