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17.17 An inverter whose equivalent load capacitance C is composed of 10 fF, contributed by the inverter transistors, and 30 fF, contributed by the wiring and other external circuitry, has been found to have a propagation delay of 30 ps. By what factor must (W/L)n and (W/L)p be increased so as to reduce tP to 15 ps? By what factor is the inverter area increased? S = 3; area increases by a factor of 3