tolong jawab yg no 11,12,13,14,15 yaa.. salah satu nya juga gk pp ^^

Nmr 11
Keliling = 2πr = 2(22/7)(14) = 88cm

Nmr 14
P.busur = 90°/360° × 2πr
______ = ¼ × 2(22/7)(7)
______ = 11cm

Nmr 15
L.juring = 120°/360° × πr²
______ = ⅓ × (22/7)(14×14)
______ = 25,3 cm²