tolong jawab no 1,2,3 pake cara

1. Luas= phi x r x r
3,14 x 10 x 10
= 314
Keliling= 2 phi r / phi d
= 3,14 x 20
=62,8
2. Luas= phi x r x r
= 22/7 x 21 x 21
= 1386
Keliling= 2 phi r/ phi d
= 22/7 x 42
=132