The sector of a circle has radius of 21 cm and central angle 180o. Find its perimeter? Choose the correct choice:	A) 91.5	B) 92	C) 108	D) 94	E) 95
Perimeter of the sector = length of the arc + 2(radius)   = (135/360 * 2 * 22/7 * 21) + 2(21)   = 108 cm   Answer: Option 108
<result>C</result>
The sector of a circle has radius of 21 cm and central angle 180o. Find its perimeter?