Diameter and Radius

Change the radius to measure = 2. What is the measure of the diameter when the radius = 2?

Change the radius to measure = 2.3. What is the measure of the diameter when the radius = 2.3?

Change the radius to measure = 3.07. What is the measure of the diameter when the radius =3.07?

Change the radius of the circle to measure = 4.06. What is the diameter of the circle when the radius = 4.06?

What number would I need to multiply the radius of any circle by to equal the diameter of that circle?