tolong ya kak pakai cara

1. r=7
l=πrr= 22/7×7×7 =154
2. r= 10
l= πrr = 3,14×10×10 = 314
3.r = 28
l= πrr = 22/7 ×28×28=2464
4.r= 36
l= πrr = 3.14×36×36 =4.069,44