Solution:

Radius of the sphere, r = 9 cm

Volume of the sphere, V = (4/3)r³

= (4/3)××9³

= 12××81

= 972 cm³

Diameter of the wire = 2 mm

So radius of the wire = 2/2 = 1 mm = 0.1 cm

Since the sphere is melted and drawn into a wire, volume remains the same.

Volume of the wire, r²h = 972

×0.1² ×h =972

h = 972/0.1²

h = 972/0.01

h = 97200 cm

h = 972 m

Hence the length of the wire is 972 m.