How Long Will It Take a Sample of Radioactive Substance $\mathrm { A } ( \mathrm { t } ) = 650 \mathrm { e } ^ { - 0.189 t }$

question 180

Multiple Choice

How long will it take a sample of radioactive substance to decay to half of its original amount, if it decays according to the functi $\mathrm { A } ( \mathrm { t } ) = 650 \mathrm { e } ^ { - 0.189 t }$ , where t is the time in years? Round your answer to the nearest
Hundredth year.

• A) 3.67 years
• B) 34.27 years
• C) 122.85 years
• D) 37.94 years