Steady-state conditions exist in the circuit shown in Figure P5.7 at $t<0$. The switch is closed at $t=0$.
$$
\begin{aligned}
V_1 & =12 \mathrm{~V} & & R_1=0.68 \mathrm{k} \Omega \\
R_2 & =2.2 \mathrm{k} \Omega & & R_3=1.8 \mathrm{k} \Omega \\
C & =0.47 \mu \mathrm{~F} & &
\end{aligned}
$$
Determine the current through the capacitor at $t=0^{+}$, just after the switch is closed.