We are given the function: \(\displaystyle{f{{\left({t}\right)}}}={6}{\left({0.84}\right)}^{{t}}\)

The function is of the form \(\displaystyle{y}={a}{\left({1}-{r}\right)}^{{t}}\), where \(1-r<1\), so it represents exponential decay.

We determine the rate of decay: \(1-r=0.84\)

\(r=1-0.84\)

\(r=0.16\)