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【简答题】
(1)考古发掘出的铜器表面往往有一层厚厚的铜绿〔主要成分Cu 2 (OH) 2 CO 3 〕，试用化学方程式解释铜绿形成的原因。 (2)为什么高档电器的铜质插孔、插头表面要镀上价格比铜昂贵但导电性又不如铜的金？ (3)不法商贩中掺入铜打制“纯金”饰品出售。如何识别这种假冒“纯金”戒指。 (4)许多资源都是不可再生的，每个公民都应树立保护资源的观念。下列做法不利于保护金属资源的是 ____________。(填选项字母) A.采取各种有效防锈方法避免金属锈蚀 B.用塑料代替钢和其他合金制造管道 C.私挖、滥采矿物 D.回收利用铝制饮料罐
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【单选题】听力原文：M: Where is Tao Jian? W: I don't know. I think she is at home. Q: Who's at home? (19)
A.
I am.
B.
We don't know.
C.
Tao Jian.
【简答题】Maria is good in a team and she gets on well with her colleagues. She is extremely ________. She is never late for meetings -- she is always ________ . She is very _______; she always meets deadlines....
【简答题】Laura is my cousin. She works at a radio station. She thinks it's an interesting job. Today I will 1 you about her life . Laura says she is very busy 2 Monday to Friday. She usually gets up at 6: 30 a...
【多选题】实现良好的焊接应具备的条件
A.
被焊的金属应具有良好的可焊性。
B.
被焊的金属表面和焊锡应保持清洁接触。
C.
应选用助焊性能适合的助焊剂。
D.
选择合适的焊锡。
E.
保证足够的焊接温度。
F.
要有适当的焊锡时间。
【单选题】听力原文：M: Where is Tao Jian? W: I don't know. I think she is at school. Q: Who's at school? (21)
A.
I am.
B.
It's at home.
C.
Tao Jian is.
【单选题】听力原文：M: Where is Tao Jian? W: I don't know. I think she is at school. Q: Who's at school? (19)
A.
I am.
B.
It's at home.
C.
Tao Jian is.
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