A circle has a radius of 12.6 cm. What is the exact length of an arc formed by a central angle measuring 120°?
\(\frac{\text{arc length}}{\text{circumference}}=\frac{\text{central angle measure}}{360^{\circ}} \\~\\ \frac{\text{arc length}}{2\pi * 12.6}=\frac{120^{\circ}}{360^{\circ}} \\~\\ \text{arc length}=\frac{120^{\circ}}{360^{\circ}}(2\pi *12.6)=\frac{42\pi}{5}\approx26.389 \text{ cm}\)
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