If $I=5\mathrm{.}00u(-t)mA,$ obtain an expression for $1^{}$ as labeled in the circuit given which is valid for all $t>0.($Round the final answers to four decimal places.$)($Include a minus sign if necessary.$)$

The expression for $q^{}$ valid for all $t>0$ is $q,e^{Bt}$ I $tA,$ where $B=s^{-1}.$