tolong yang jago matematika nomer 3 bagian a sampai d

K = 2 × phi × r
15 = 2 × 22/7 × r
r = (15×7)/44
r = 105/44
r = 2,38

K = 2 × phi × r
44 = 2 × 22/7 × r
r = (44×7)/44
r = 7

K = 2 × phi × r
110 = 2 × 22/7 × r
r = (110×7)/44
r = 17,5

K = 2 × phi × r
88 = 2 × 22/7 × r
r = (88×7)/44
r = 14

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