Answer:
C
Step-by-step explanation:
The arc length s is calculated as
s = circumference × fraction of circle
= 2πr × [tex]\frac{\frac{7\pi }{9} }{2\pi }[/tex]
= 2π × 18 × [tex]\frac{\frac{7\pi }{9} }{2\pi }[/tex]
Cancel the 2π on numerator/ denominator
= 18 × [tex]\frac{7\pi }{9}[/tex] = 2 × 7π = 14π → C
