下列不属于涂料辅助成膜物质的是()。
A.油料
B.防锈颜料
C.天然树脂
D.溶剂
参考答案:D
用适当的数字和符号填空
(1)氖气 ______;
(2)氯化亚铁中铁元素显+2价 ______;
(3)硝酸根离子 ______;
(4)2个氯原子 ______;
(5)导电性最好的金属 ______;
Used to TV shows, _____ everything is quick and entertaining, many people do not have the patience to read a book that requires thinking.
A.which
B.what
C.where
D.when