A couple of two-way radios were purchased from different stores. Two-way radio A can reach 3 miles in any direction. Two-way radio B can reach 6.44 kilometers in any direction.

Part A: How many square miles does two-way radio A cover? Use 3.14 for π and round to the nearest whole number. Show every step of your work. (3 points)

Part B: How many square kilometers does two-way radio B cover? Use 3.14 for π and round to the nearest whole number. Show every step of your work. (3 points)

Part C: If 1 mile = 1.61 kilometers, which two-way radio covers the larger area? Show every step of your work. (3 points)

Part D: What is the scale factor of the circle for two-way radio A to the circle for two-way radio B? (3 points)