Material aluminum copper iron nichrome platinum silver Resistivity (p 92 m) 2.82 x 10-8 1.72 x 10-8 9.68 x 10-8 100 x 10-8 10.0 x 10-8 1.63 x 10-8 Assume the problems below are at the same temperature as the table above. 1. What is the resistance of a 20 m silver wire with a 2.2 mm diameter? 2. A silver wire with a 2 mm diameter has a resistance of 150 ohms. How long is the wire? 3. A 220 m long aluminum wire has the same resistance and cross-sectional area as a Silver wire. What is the length of the silver wire? 4. A 20V potential difference is maintained across a 2m length wire that has a diameter of 0.5mm. If the wire is made of material that has a resistivity 7x10^-8Qm, what is the current(I) in the wire? 5. A copper wire has a resistance R. If both its length and diameter are doubled then what will be its new resistance, R?