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(a) Electrical energy is transmitted at very high voltages and low current.
(i) Describe how the high voltages are attained.
(ii) State two reasons why thick aluminium wires are preferred to copper wires for transmission over long distances.
(b) Figure 4 shows an electric cooker connected to the mains supply. X, Y and Z are the mains wires.
State with a reason the name of wire Y.
(c) A student has some coloured bulbs rated 60W, 240V to be connected for decorations.
(i) State the number of such bulbs that can be connected normally to 249V supply through a 5A fuse.
(ii) If the cost of electric energy is Ksh. 3.00 per kWh, determine the cost of running the bulbs in (c) (i) for 5 hours daily for 20 days.