A Sample of 200 Grams of Radioactive Substance Decays According $\mathrm { A } ( \mathrm { t } ) = 200 \mathrm { e } ^ { - 0.031 \mathrm { t } }$

Multiple Choice

A sample of 200 grams of radioactive substance decays according to the function $\mathrm { A } ( \mathrm { t } ) = 200 \mathrm { e } ^ { - 0.031 \mathrm { t } }$ where t is the time in years. How much of the substance will be left in the sample after 40 years? Round your answer to the
Nearest whole gram.

A) 1 gram
B) 2465 grams
C) 58 grams
D) 0 grams