Step 1: Understand that resistivity is a property of materials that indicates how much they resist the flow of electric current.
Step 2: Know that the unit of resistance is Ohm (Ω).
Step 3: Recognize that resistivity is defined as resistance per unit length and area.
Step 4: Realize that when you combine the units for resistance (Ohm) with length (meter) and area (square meter), you get Ohm-meter (Ω·m) as the unit of resistivity.
