Which part of the bulb is an insulator?

To protect the user, part(s) _______ of the plug as shown in the figure must be made of electrical insulators.

Label the dry cell in the correct order.

Which of the following statements are correct?

(i) Human body is a good conductor of electricity.

(ii) The air gap surrounding an electric circuit acts as a conductor.

(iii) Silver conducts electricity better than any other metal.

(iv) When electricity lights up a bulb, no heat is produced.