The answer will depend on what the 12 mm measures. If the object is 12 mm in diameter, it is 37.7 mm around.
you measure the thickness of a book in inches.
one complete circular movement made by one object around another object
6 millimeters
The Correct Answer would be 8 millimeters.8 millimeters
22 inches to 16 inches is a decrease of six inches.
A diameter is a property of circular objects. "12 inches" is not a circular object and so cannot have a diameter.
rotation
An orbit. In fact, orbits are not usually exactly circular. They are "elliptical".
An object that is three millimeters would be very, very tiny. For citizens in the US, it is easier to conceive of the millimeter in terms of inches. Three millimeters is equal to approximately 0.11 inches. Kidney stones are an example of something that can come in sizes this small.
Diameter is the width of a circular or spherical figure or object. Something 180 inches in diameter is also 180 inches in width or thickness.
A force that acts on a body moving in a circular path and is directed around the object which the body is moving
you measure the thickness of a book in inches.
one complete circular movement made by one object around another object
13.7 millimeters
Centripetal force is necessary to keep an object in a circular path.
It is the distance around an outside of a round 180 circular object
13.7 millimeters