A wire (length = 2.0 m, diameter = 1.0 mm) has a resistance of 0.45 Ω. What is the resistivity of the material used to make the wire?
a. 5.6 × 10⁻⁷ Ω·m
b. 1.2 × 10⁻⁷ Ω·m
c. 1.8 × 10⁻⁷ Ω·m
d. 2.3 × 10⁻⁷ Ω·m
e. 7.1 × 10⁻⁷ Ω·m