A. Barry Landau's friend Betty Currie's cousin C. Bill Clinton's dog D. George Washington's play-date.
A. 骨料表面有酸性污染物 B. 骨料中含非晶体二氧化硅 C. 用于制作盛酸性介质的设备
A. 正确 B. 错误
A. allow B. cause C. forbid D. keep