Respuesta :

Answer:

7.8

Step-by-step explanation:

The diameter is the full length across a circle. The radius is always half the diameter. if you divide 15.6 by 2 (to get half), we get 7.8. If this does not answer the question, let me know so I can edit

16.74469; (123/360)(2pi*7.8)
123 is from 180-57
and 7.8 is the radius cux 15.6/2
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