The table shows four different materials and their resistivity.

Material	Resistivity $(\Omega \mathrm{m})$
Material 1	$1.62 \times {10}^{-8}$
Material 2	$100 \times {10}^{-6}$
Material 3	$6.84 \times {10}^{-8}$
Material 4	$44 \times {10}^{-6}$

Which material is the best conductor of electricity?

What does the symbol mean in an electric circuit?

A current of $1 \mathrm{A}$ flows through an electric bulb for $5 \mathrm{minutes}$.

What is the amount of electric charge that flows through the bulb? Show your calculation.

The picture shows an electric circuit.

Which of these is true about the circuit?

Will there be any change in the ammeter reading if the length of the wire in the circuit is doubled? Explain your answer.

Suresh arranges the electric circuit shown below to measure the current flowing through and the potential difference of a bulb.

Is the circuit correct? If not, then identify the mistake.