forces: forces applied to an object in opposite directions that are not equal in size. Unbalanced forces result in a change in motion. friction: the force that opposes the motion or tendency toward motion of two objects that are in contact.
Answer is C. Light is measured by its wavelength (nanometers) or frequency (hertz).
In a closed system, energy in form of heat (work) can be exchanged but not matter.
The answer to your question is C.
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To make sure I don’t has 35 012345 bishops