Which conversion factor should you multiply by when converting degrees to radians?

Convert 120° to radians in simplest form.

Are 5π/3 and -π/3 coterminal? Provide numeric reasoning.

Given two angles A = 810° and B = -450°, evaluate whether A and B are coterminal and provide the numeric justification.

A circular track has radius 3 meters. If a runner covers 6 meters along the circumference, what is the central angle in radians and in degrees (rounded to two decimal places)?