Why are copper and aluminium wires usually used for electricity transmission?

Explain the following : (a) Why is tungsten used almost axclusively for filament of incandescent lamp ? (b) Why are the conductors of electric heating devices, such as toaster and electric irons, made of an alloy rather than a pure metal ? ( c) Why is the series arrangement not used for domestic circuits ? (d) How does the resistance of a wire vary with its cross-sectional area ? (e ) Why are copper and aluminimum wires usually employed for electricity transmission.

Give reason for the following: (i) Electric bulbs are usually filled with chemically inactive gases like nitrogen and argon. (ii) Copper and aluminium wires are usually employed for electricity transmission. (iii) Fuse wire is placed in series with the device.

Give reasons: Aluminium wire is used to make transmission cables.