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Answer:</h2>
An angle measures how how much you have to rotate one line called <em>initial side</em> so it lies on the top of other line called the <em>terminal side. </em>Angles whose vertex is located at the origin having the initial side on the positive x-axis is said to be in standard position. On the other hand, coterminal angles are angles in standard position having the same terminal side. In this way, for the angle:

The 3 represents how many times the species multiplies.
Do you think you could find a better picture so that I can see the complete question
(M+n)/p=r
Multiply by p
M+n=pr
Minus M
n=pr-M