The rate at which a substance grows is given by $R^{\text{'}}(x)=195e^{0\mathrm{.}4x},$ where $x$ is the time $($in days$).$ What is the total accumulated growth during the first $3\mathrm{.}5$ days?

Set up the definite integral that determines the accumulated growth during the first $3\mathrm{.}5$ days.

Growth $={\displaystyle \underset{0}{\overset{\phantom{}}{}}}1dx$

$($Type exact answers in terms of $e.)$