Urgent! Please help with Resistivity!

These are questions on resistivity and I can't quite work out the right answers. Please help!

1. The filament of a 240V 60W lamp is made from 600mm of tungsten wire. At its working temperature the resistivity of tungsten is 7.0 x 10^-7 Ohm m. What is the diameter of the wire.

2. Conducting putty is a material which is similar to plasticine but is an electrical conductor. A student rolls some of the putty into a cylindrical shape which is 60mm long and has a diameter of 20mm. He then rolls it into a new cylindrical shape which has a diameter of 10mm.
a) what is the new length
b) what is the ratio (new resistance)/(old resistance)

Thank you.

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