Does anyone know it?

Answer:
4π/5
Step-by-step explanation:
APC angle is equals to AC arcle.
The inscribed angle is 2π/5. To discover an inscribed angle, the formula is:
IA = IC/2
IA = inscribed angle
IC = central angle
IA = 2π/5
[tex]\frac{2\pi}{5} = \frac{IC}{2} \\\\\ 5IC = 4\pi \\\ IC = \frac{4\pi}{5}[/tex]
IC angle = AC arcle
AC = 4π/5
I hope I've helped you.