用3A分子筛来吸附二氧化碳气体中的水,而尽可能地不吸附二氧化碳,这是利用吸附剂()A 发布时间:2019-11-05 18:39 │ 来源:www.tikuol.com 题型:单项选择题 问题: 用3A分子筛来吸附二氧化碳气体中的水,而尽可能地不吸附二氧化碳,这是利用吸附剂()A、有高度选择性B、有高的吸附活性C、有一定的机械强度和物理特性D、有良好的化学稳定性、热稳定性
题型:单项选择题 如图,A、B分别是甲、乙两小球从同一地点沿同一直线运动的v-t图象,根据图象可以判断( )A.两球在t=2s时速率相等B.两球在t=8s时相距最远C.两球运动过程中不会相遇D.甲、乙两球做初速度方向相反的匀减速直线运动,加速度大小相同方向相反 查看答案
题型:单项选择题 根据对话内容及方框中所给的句子补全对话.其中有一项是多余的。A. I'll feel shy B. it'll be easier some day. C. you have to be brave,just speak aloud. D. you can always ask for help. E. I'm afraid to speak F. I'm not looking forward to it.A:Hi Joyce. What's up?B: Hi. Clara. I'm on my way to the English corner. We are starting a lesson on English-speaking skills,and 1._______A: Really? Why not?B:I am not brave enough to speak English, so 2._________What should I do?A:Oh, don't bc nervous. If you really want to improvc your English-speaking skills,3.________B: But 4.________if l make mistakes when speaking to others.A: Don't be afraid to make mistakes because that is part of the process of English learning. Gradually you'II get more confident and 5.B: Thank you for your advice. I will do my best. Oh, I'II be late. Bye!A: Bye! 查看答案