A 4200 resistor is connected across a charged 0.750 nF capacitor. The initial current through the resistor, just after the connection is made, is measured to be 0.275 A .

a) What magnitude of charge was initially on each plate of this capacitor?Express your answer in microcoulombs.

b) How long after the connection is made will it take before the charge is reduced to 1/e of its maximum value?Express your answer in microseconds.