Question

which of the contexts below represents exponential decline or decay?
answer
the amount of a certain medication in a persons bloodstream decreases by $\frac{2}{5}$ every day.
a coin collection appreciates at a rate of 2.4% per year.
snow was melting at a rate of 2.5 inches per hour.
a population of 250 bacteria doubles every month.

Explanation:

Answer:

The amount of a certain medication in a person's bloodstream decreases by $\frac{2}{5}$ every day.