Jimmy Volt, an EECS alum, wishes to dim the lights in his apartment in Berkeley, CA (i.e., Vs=2 120 V, =377 rad/s). He would like to dim his 75 W lightbulb to 1/3 its rated power (25 W). Shown in Figure 1 is a controlled full-wave rectifier that he has constructed. The turn-on time of the SCRs are delayed by a time td after the zero crossing of the grid voltage