Volume of the silver = 66 cubic centimetres
Diameter of the wire = 1 mm => r = 0.5 mm = 0.05 cm
Assume the length of the wire is l.
Volume of the wire = Volume of the silver
πr2 l = 66
22/7 x (0.05)2 x l = 66 => l = 84 metres
Hence the length of the wire is 84 metres.