Consider yourself a research scholar in the forensic science department studying the age of a dead…

Consider yourself a research scholar in the forensic science department studying the age of a dead biological sample. During one of the studies, you found that the sample decomposed by following first order kinetics. If $50\%$ of the sample is decomposed in $120\text{ minutes}$, how long will it take for $90\%$ of the sample to decompose?