Question 45A wire 4m long and of cross sectional area 2 × 10-8m2 has a resistivity of 5Ω calculate its resistivityA.4 × 107Ω/mB.2.5 × 107Ω/mC.4 × 10-8Ω/mD.2.5 × 10-8Ω/mObjective Show full explanation