The electricity that is delivered to our homes from regional generating stations uses high voltage
to increase the safety of transmitting electricity
to keep the available power the same despite the low current
to induce magnetic fields in the wires
to increase the magnetic field produced by the current

to keep the available power the same despite the low current".

Explanation:

From the power stations the electricity is transmitted using transformers to increase the voltage for power long distances.  At further substation, it is delivered further using smaller voltage lines.  Electricity is supplied at high voltage to increase the efficiency and minimize the lost occurring during supplying to longer distance.  

it would only be the stuff in module eight so you need to study all the lessons in that you also could check the flvs

hope this : )