A.3 B.4 C.5 D.10
A.①-②-③-④-⑤-⑥-⑦-⑧ B.④-②-③-①-⑤-⑥-⑦-⑧ C.②-⑤-③-④-①-⑥-⑦-⑧ D.①-②-④-⑤-③-⑥-⑦-⑧
A.0.5 B.1 C.5 D.20
A.铁 B.铜 C.木 D.不锈钢