Answer:
[tex]arc\ CD=83.5\°[/tex]
Step-by-step explanation:
Let
[tex]\theta[/tex] -----> the central angle of arc CD
we know that
[tex]sin(\frac{\theta}{2})=\frac{(12.7/2)}{9.06}=\frac{12.07}{18.12}[/tex]
[tex]\theta/2=arcsin(\frac{12.07}{18.12})=41.77\°[/tex]
so
[tex]\theta=(2)41.77\°=83.5\°[/tex]
The measure of arc CD is equal to the angle theta by central angle
[tex]arc\ CD=83.5\°[/tex]
