A resistor and capacitor are connected in series across an ac generator. The emf of the generator is given by v(t) = V0cosωt, where V0 = 120V, ω = 120π rad/s, R = 400Ω, and C = 4.0μF. (a) What is the impedance of the circuit? (b) What is the amplitude of the current through the resistor? (c) Write an expression for the current through the resistor. (d) Write expressions representing the voltages across the resistor and across the capacitor