The formula for the arc lenght is
[tex]\begin{gathered} s\text{ = }\frac{\alpha\pi r}{180} \\ \alpha\text{ is the angle of the arc} \\ r\text{ is the radius} \end{gathered}[/tex]
Substituting
[tex]\begin{gathered} s\text{ = }\frac{\alpha\pi}{180}r\text{ = }\frac{80}{180}\pi(7in) \\ c\text{alculating we get} \\ s=\text{ }\frac{28}{9}\pi\text{ in } \\ s=\text{ 9.77 in} \end{gathered}[/tex]
