3.14 × 2² = 12.56
3.14 × 3² = 28.26
3.14 × 4² = 50.24
3.14 × 5² = 78.5
3.14 × 6² = 113.04
3.14 × 7² = 153.86
3.14 × 8² = 200.96
3.14 × 9² = 254.34