題組內容

B. 鑄砂黏土含量試驗：試驗前鑄砂樣本磅重 50.00g，試驗時洗淨黏土後磅重 47.25g，則鑄砂黏土含量為: ____1___% B. 鑄砂黏土含量 = [(50.00 - 47.25)/50] × 100% = ___2___%

2.