Answer :

For this problem we know that the radius is 7.9cm and the angle between C and D is 66.4ª. We also want to find the arclenght so we can use the following formula:

[tex]AL=\frac{x}{360}\cdot2\pi r[/tex]

Where x is the angle and r the radius r=7.9cm. So then replacing into the function we got:

[tex]AL=\frac{66.4}{360}\cdot2\pi(7.9cm)=9.16\operatorname{cm}[/tex]

And if we round to the nearest tenth we got 9.2 cm