In an industrial timing circuit, an 80 μF80\ \mu\text{F}80 μF capacitor is fully charged and then allowed to discharge through a 75 kΩ75\ \text{k}\Omega75 kΩ resistor. What fraction of the capacitor's original charge has been transferred to the resistor 9.0 s after the discharge begins?
0.220.220.22
0.490.490.49
0.630.630.63
0.780.780.78
