A 1.00-F capacitor, initially charged to 12 V, discharges when it is connected in series with a

Question:

A 1.00-μF capacitor, initially charged to 12 V, discharges when it is connected in series with a resistor.
(a) What resistance is necessary to cause the capacitor to have only of its initial charge 1.50 s after starting?
(b) What is the voltage across the capacitor at if the capacitor is instead charged by the same battery through the same resistor?