tolong dong pake cara ya Tyy

keliling =πd
1. 22/7 . 7 = 22
2. 22/7 . 21 = 66
3. 22/7 . 28 = 88
keliling = 22 + 66 + 88 = 176 cm
Luas =πr²
1. 22/7 . 3,5 . 3,5 = 38,5 cm²
2. 22/7. 10,5 . 10,5 = 346,5 cm²
3. 22/7 . 14.14 = 616 cm²
Luas diarsir = 38,5 cm + (616-346,5)
= 38,5 + 269,5
= 308 cm²