圆周长:直径 × π C = π·d圆面积:π /4 × 直径^2 S = π /4 × d^2圆柱体积:底圆面积 × 高 V = π /4 × d^2 × h 周长:C = π·d = 3.14 × 8 ≈ 25.12 (米)体积:V = π /4 × d^2 × h = 3.14/4 × 8^2 × 2 ≈ 100.48 (立方米)