Respuesta :

The arc length by definition is given by:
 S = r * theta
 Where:
 R: radius
 Theta: central angle
 For this case we have that the arc length is:
 S = (30/180) * 9 * pi
 S = (3/2) pi
 Answer:
 
The length of the arc shown in red is:
 
S = (3/2) pi