Elementary Geometry for College Students (6th Edition)

$\frac{8}{3} \pi$ in
AB is the minor arc of the circle We need to find out the length of AB In a circle whose circumference is c, the length l of an arc whose degree measure is m is given by l =$\frac{m}{360}$ * c Therefore for given circle c = 2$\pi$ r = 2$\pi$ * 8 = 16$\pi$ given m =60$^{\circ}$ Therefore lAB = $\frac{m}{360}$ * c = $\frac{60}{360}$ * 16$\pi$ =$\frac{8}{3} \pi$ in