皮皮学，免费搜题
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【单选题】
下了说法正确的是( )。A.
乙烯密度比空气大
B.
乙烯分子的空间结构是正四面体
C.
乙烯较为活泼，典型反应是加成反应
D.
乙烯可通过氧化反应得到聚乙烯
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皮皮学刷刷变学霸
举一反三
【单选题】WebSocket 协议由哪个组织负责开发[1.0] prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace>
A.
WHATWG prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace>
B.
W3C prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace>
C.
IETF prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace>
D.
共同开发
【单选题】“Have you seen Ann at the concert?”“No, but she said she would come,?”()
A.
didn’t she
B.
wouldn’t she
C.
did she
D.
would she
【单选题】— Have you seen Shirley since she moved away? — Yes. I’ve seen her several times. She comes back to visit us ______.
A.
at any moment
B.
from time to time
C.
in no time
D.
sooner or later
【简答题】基带同轴电缆,其特性阻抗为____欧姆,其金属网状织物屏蔽层材料通常为铜,主要用于__________。 宽带同轴电缆,其特性阻抗为____欧姆,其金属网状织物屏蔽层材料通常为___,主要应用于计算机网络。
【单选题】She told them where she ______ her son.
A.
has last seen
B.
had last seen
C.
last seen
D.
was last seeing
【单选题】She stared at the painting,wonder where she ____it.
A.
saw
B.
has seen
C.
sees
D.
had seen
【简答题】A.She agrees with the man. B.She hasnt seen Kevin recently. C.She thinks Kevin will be late. D.She doesnt know what the man means.
【单选题】She______ not have seen you yesterday, for she was not there.
A.
could
B.
might
C.
should
D.
must
【单选题】妊娠合并心脏病,产科护理原则
A.
产前严密观察生命体征
B.
产前严密观察宫缩和胎心音
C.
分娩期第二产程应尽快结束
D.
产后应立即在产妇腹部放置砂袋
E.
以上均对
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