Which equation is used to calculate the circumference of a circle?

The circumference of a circle is a measure of the distance around it and can be calculated using the equation C = 2πR. In this formula, C represents the circumference, π (pi) is a mathematical constant approximately equal to 3.14159, and R stands for the radius of the circle. The radius is the distance from the center of the circle to any point on its circumference.

By multiplying the radius (R) by 2 and then by π, you effectively account for the entire circular path around the center, resulting in the total circumference. This equation is foundational in geometry and is applicable to any circle, regardless of its size, making it a crucial concept to understand in various mathematical and scientific contexts.

In contrast, the other options involve incorrect or unrelated formulas for circumference or area. For example, the option that uses only πR does not represent the complete distance around the circle, and the formula involving R^2 pertains to the area of the circle, not its circumference.