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【单选题】
能反应市场发展变化的历史与现实过程的二手资料属于A.
原始资料
B.
静态资料
C.
加工资料
D.
动态资料
拍照语音搜题，微信中搜索"皮皮学"使用
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皮皮学刷刷变学霸
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【简答题】(A) 根据句意及首字母提示填空。 41. She is a s_________ girl. She is afraid of speaking in public. 42. The boy is funny. He always tells us some j_________. 43. He didn’t a_________ my gift at his birthday party. 4...
【简答题】【化学——选修2：化学与技术】（15分） 自来水生产的流程示意图见下： （1）混凝剂除去悬浮物质的过程 （填写序号） ①只是物理变化 ②只是化学变化 ③是物理和化学变化 FeSO 4 ·7H 2 O是常用的混凝剂，它在水中最终生成 沉淀。 （2）若要除去Ca 2+ 、Mg 2+ 可以往水中加入石灰和纯碱，试剂填加时先加 后加 ，原因是 。 （3）氯气消毒，是因为它与水反应生成...
【简答题】现有一含微量铜、铅、锌的水样,要测定这些组分,若用离子交换法富集分离这些阳离子,交换柱中要装填什么类型的交换剂?交换柱使用一定时间后怎样进行交换剂的再生?写出交换和再生反应通式?
【单选题】听力原文：W: I wonder what' s happened to Jerry. He hasn't been around for at least 2 weeks. M: He took a leave to see his mother in Europe. Q: Why is Jerry away? (18)
A.
He is attending his sick mother at home.
B.
He is on a European tour with his mother.
C.
He is at home on sick leave.
D.
He is in Europe to see his mother.
【简答题】根据电话中的对话内容,填写下面所缺的单词,每空一词,Teacher-T, Sam-S T:Hello,5346880 S: Hello,(1) is Sam. Could I (2) to the head, please? T: (3)(4) for a minute, please. I'm sorry he is (5) at the moment. can I(6) a m...
【简答题】1 He is a stamps l______(爱好者),so he enjoys collecting stamps at his free time. 2 Fish is her f_____(最喜欢的)food. 3 Chirstmas is very popular in China, e______(尤其是)for young people. 4 You should pay for ...
【多选题】装离子交换柱的要求
A.
不能干胶装柱
B.
树脂填充到离子交换柱中，用水充分地逆冲洗涤，把树脂中的微粒、夹杂的尘埃溢流除去，同时驱逐树脂层的气泡，使交换柱内树脂颗粒填充均匀
C.
停止逆洗，待树脂沉降后，缓慢通水，压实
D.
树脂层之上一般应保持有液层，避免树脂干裂
E.
树脂层中若有气泡，会形成交换时的短路，使交换不完全。
【简答题】Do you have a ver y strict teacher ? I do. He is Mr. Grand , our geography teacher. We call him “Mr. Grumpy” because he often gets angry ( 生气的 ) . Not finish your geography homework ? Good luck to you...
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