Jawab ini beserta caranya​

1. d = 42 cm

rumus keliling =

jadi,

K = 22/7 × 42

= 132 cm

2. r = 7 cm

d = r × 2 = 7 × 2 = 14 cm

K = 22/7 × 14 = 44 cm

3. d = 28 cm

K = 22/7 × 28 = 88 cm