Given thatBattery voltage v=13.8 voltsPower consumed by each light is 20 wattLet R_(1),R_(2),R_(3) are the resistances of each bulbThen total power consumed is given by (a).When three lights are connected in parallelThen total reciprocal of resistance{:[(1)/(R_(eq))=(1)/(R_(1))+(1)/(R_(2))+(1)/(R_(3))],[" From "],[P=(v^(2))/(R_(eq))],[P=V^(2)[(1)/(R_(1))+(1)/(R_(2))+(1)/(R_(3))]],[P=(v^(2))/(R_(1))+(v^(2))/(R_(2))+(v^(2))/(R_(3))],[P=P_(1)+P_(2)+P_(3)],[P=20+20+20],[P=60 watt]:}Since, three lights are identicalPower consumed when connected in parallel is 60W(b).When three lights are conne ... See the full answer