Is air a good or bad conductor of heat ?

Out of the following objects, mention which are good conductors of heat and which are bad conductors of heat- iron rod, aluminium sheet, plastic container, wooden table, steel spoon.

Explain why a good conductor of heat is also a good conductor of electricity?

Explain,why metals are good conductors of heat and electricity?

Same potential difference is applied to a good conductor and a bad conductor of same dimensions. Which one of them will proeduce more heat and why?

Name two metals which are good conductors of both heat and electricity.