1 π= 3.14
2 π= 6.28
3 π= 9.42
4 π= 12.56
5 π= 15.7
6 π= 18.84
7 π= 21.98
8 π= 25.12
9 π= 28.26
10 π= 31.4
11 π= 34.54
12 π= 37.68
13 π= 40.82
14 π= 43.96
15 π= 47.1
16 π= 50.24
17 π= 53.38
18 π= 56.52
19 π= 59.66
20 π= 62.8
21 π= 65.94
22 π= 69.08
23 π= 72.22
24 π= 75.36
25 π= 78.5
26 π= 81.64
27 π= 84.78
28 π= 87.92
29 π= 91.06
30 π= 94.2
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