Why do we use copper and aluminium wire for the transmission of electric current?

Explain the term resistance. Give its $SI$ unit of measurement.

The $I-V$ graphs of two resistors,and their series combination,are shown below. Which one of these graphs represents the series combination of the other two? Give reasons for your answer.

Three incandescent bulbs of $100\, W$ each are connected in series in an electric circuit. In another circuit,another set of three bulbs of the same wattage are connected in parallel to the same source. Now,if one bulb in both the circuits gets fused,will the rest of the bulbs continue to glow in each circuit? Give reasons.

Why is very less heat generated in long electric cables than in filaments of electric bulbs?

Why is parallel arrangement used in domestic wiring?