AB = 6, which is 3/ 16 of the circumference.
∴ perimeter = ab ÷ 3/16 = 6 ÷ 3/16 = 32
∵ABCD is quadrilateral
∴AB=CD
∴BC=32-2*AB=32-6*2= 10
2、
∫AC+BD = 36
∴OC+OD=36÷2= 18
∫AB = 1 1
∴CD= 1 1
∴△OCD perimeter = OC+OD+CD =18+11= 29.