im giving 40 points!!!!!!! help help
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Answer:
Pi x (2 x radius) = C
Step-by-step explanation:
Learn that the perimeter of a circle has its own special name, called "circumference." The symbol is a capital C. It is calculated using the formula Pi x diameter, or 3.14 x d = C. It can also be calculated by Pi x (2 x radius) = C or 3.14 x (2 x r) = C.