radius=17.22 centimeters
Explanation
we can use the formula for length of an arc
[tex]l=2\pi\text{ r }(\frac{\Theta}{360})[/tex]where l is the length of the arc, r is the radius, and theta is the angle in degrees
then
Let
[tex]\begin{gathered} \Theta=62.8\~ \\ l=18.4 \end{gathered}[/tex]now, replace
[tex]\begin{gathered} l=2\pi\text{ r }(\frac{\Theta}{360}) \\ l=2\pi\text{ r }(\frac{62.8}{360}) \\ 18.4=2\pi r(0.17444) \\ 18.4=0.34\text{ }\pi\text{ r} \\ \text{divide both sides by 0.34 }\pi \\ \frac{18.4}{0.34\pi}=\frac{0.34\text{ }\pi\text{ r}}{0.34\pi} \\ 17.22=\text{radius} \end{gathered}[/tex]I hope this helps you