问题
单项选择题
某些复合树脂充填后日久易变色,是由于其中成份含有()
A.甲基丙烯酸甲酯(稀释剂)
B.N,N-二羧乙基对甲苯胺(促进剂)
C.双酚A甲基丙烯酸缩水油脂类
D.2,6-二羧丁基对甲酚(阻聚剂)
E.都不正确
答案
参考答案:C
某些复合树脂充填后日久易变色,是由于其中成份含有()
A.甲基丙烯酸甲酯(稀释剂)
B.N,N-二羧乙基对甲苯胺(促进剂)
C.双酚A甲基丙烯酸缩水油脂类
D.2,6-二羧丁基对甲酚(阻聚剂)
E.都不正确
参考答案:C
读下面短文,弄懂大意,然后选择所给单词或短语并用其适当形式填空。 | |
breakfast. At school I have a break at half past ten. I (3) at school at a quarter to one at noon. In the afternoon, I play games with my classmates and then (4) the classroom. At about five (5) , I (6) . I (7) at 6: 10 in the evening, then (8) TV for two (9) . After that I do my homework. And I (10) at 10: 00. |