酸蚀刻法复合树脂修复的粘结机制是()
A.螯合
B.化学键
C.范德华力
D.机械粘结
E.结合共聚
参考答案:D
为了探究惯性现象,小明同学用胶水将盛有水的小碗固定在小车上,如图是他拉着小车在水平桌面上运动的瞬间所发生的现象示意图,此现象说明
A.水具有惯性
B.盛水的容器具有惯性
C.小车具有惯性
D.一切物体都有惯性
Speaker A: Excuse me, Mr. Black, can you spare me a few minutes There’s something I’d like to speak to you about. I won’t keep you long. Speaker B: ()。
A. What do you want to talk with
B. Yes, go ahead.
C. What’s the matter
D. Oh, nice to see you, John.