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2.2 Consider the RC circuit of Figure 9 in which a 0.1 volt input is applied for 0.5 millisecond and then the voltage goes to zero. (a) What is the time constant of this circuit. (b) Find an equation and sketch the voltage across the capacitor for the 0.5 milliseconds when 0.1 volts is applied. (c) Find an equation and sketch the voltage across the capacitor after 0.5 milliseconds when the applied voltage goes to 0. 10005 Figure 9