$3.$ Build an exponential equation for each situation $($Specifying Input and Output$)$

a$.$ Disposable income is projected to grow at an annual rate of $2\mathrm{.}9\%$

b$.$ Non$-$agriculture employment is projected to grow at $1\%$ per year

c$.$ Employment in manufacturing is projected to grow at $0\mathrm{.}2\%$ per year

$4.$ Build an exponential equation for each situation $($specifying Input and Output$)$

a$.$ The amount of caffeine in the body decreases at a $12\mathrm{.}9\%$ rate.

b$.$ A town population decreases by $8\%$ per year.

c$.$ A pollutant dumped into a lake decomposes at $23\%$ per year