1.

 Find the length of arc ACB and the area of sector OACB in each of the circles

 below. Take .

(a)

(b)

 

 

(a) Given that radius of circle is 7 cm and length of  arc ACB is 9 cm, find  (i) in degree,  (ii) in radian,  (iii) area of sector OACB.