A battery with $=12\mathrm{.}0$ V is connected in series with a $3\mathrm{.}0$ M$$ resistor, a $4\mathrm{.}0$ F capacitor, and a

switch. Before the switch is closed, there is no charge on the capacitor. The switch is closed until

there is a charge of $24\mathrm{.}0$ C of charge stored on the capacitor, and then the switch is reopened.

a$.$ Find the current through the resistor immediate after the switch was closed.

b$.$ Find the current through the resistor just before the switch was opened.

c$.$ How long was the switch closed?

d$.$ How much energy is stored in the capacitor after the switch was reopened?