A particular resistance wire has a resistance of 3 ohm per metre. Find
a) the total resistance of three lengths of this wire each 1.5 m long, joined in parallel.
b) the potential difference of the battery which gives a current of 2 A in each of the 1.5 m length when connected in parallel to the battery.
c) the resistance of 5m length of a wire of the same material, but with twice the area of cross section.