All filaments of a five-lamp receiver and additional quenching resistance are connected in series. For normal heating of all filaments, a current I = 0.3 A is required. The filament voltage of one of the lamps is V1 = 30 V, the others are V = 6 V. What additional resistance should be turned on if the supply voltage Vo = 120 V? Specify the switching circuit and select the value of additional resistances at which the lamps operate in the given modes, for the case when all lamps with a filament voltage of 6 V are connected in parallel. At what switching on will the power dissipated by additional resistances be greater?

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