Respuesta :

The area of a sector of a circle is ½ r² ∅, where r is the radius and ∅ the angle in radians subtended by the arc at the centre of the circle.

Answer:

½ pi

Step-by-step explanation:

Area of sector

= ((pi/9)/2pi) × area of the circle

= (1/18) × 9pi

= ½ pi