Double Gas Oven Electric Cookers Kitchen Appliances Range parts Tips

i need some help with these questions
1.Give two advantages for a ring main circuit
2. Explain why a cooker of total power 6kw has to have a seperate connection to the consumer unit and cannot be plugged into a ring main power circuit
3. What are substances called through which electricity passes through easily
4.what substances are called electrical insulators
5.why are eletrical wires insulated
6.why should metal frames of electrical apparatus be connected to earth
7. suppose the earth wire of a metal-framed electric fire became loose. if the live wire touched the metal frame what wud happen if you touched the flame
thanks