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【简答题】
（1）将下列各名词填在与之相对应的空格中（只需填字母）． A、挥发B、升华C、潮解E．干馏F．分馏G．吸附H．催化 ①氢氧化钠固体露置在空气中，表面变潮湿______； ②把烟煤隔绝空气加强热，分解成焦炭、煤焦油、焦炉煤气等______； ③干冰固体放置在空气中，变成二氧化碳气体______； ④活性炭放入红墨水中，红色褪去______． （2）小凯同学在复习化学基本概念和基本原理时归纳出了大多数概念常存在如下三种关系： 分析上述图示后，请你结合所学知识，判断如下三组中的概念A、B分别属于何种关系？（在空格中填写“并列关系”、“包含关系”、“相交关系”）
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举一反三
【多选题】要形成流体动力润滑，必须满足以下条件（ ）。
A.
两摩擦表面形成楔形空间
B.
两摩擦表面要有一定的相对滑动速度
C.
两摩擦表面的相对运动方向是由大端到小端
D.
必须保证持续不断的供油。
【简答题】已知 a ? b =-12 2 ，| a |=4， a 和 b 的夹角为135°，则| b |=______．
【多选题】形成流体动力润滑的必要条件是（ ）。
A.
两摩擦表面形成楔形空间
B.
充分供应具有一定粘度的润滑油
C.
具有一定的相对滑动速度，且相对运动方向是由大端指向小端
D.
润滑油温度不超过50℃
【简答题】A. equal B. matched C. proportional D. balanced
【简答题】已知点A（3，a）和点A′（b，-4）关于原点对称，则a=______，b=______．
【多选题】Situation: Jim asked Magid to come into his home. They talked about what they had been doing since Magid left the company. Magid stayed about three hours and then said, "I'd better go now." Jim got up...
A.
Magid thought that Jim should have asked him to stay longer.
B.
Magid thought that he didn't stay long enough.
C.
Magid couldn't understand why Jim thanked him for coming.
【简答题】什么是接受,构成一项有效接收应当具备什么条件?
【简答题】已知实数a，b分别满足3a 4 +2a 2 -4=0和b 4 +b 2 -3=0，求 4 a 4 + b 4 的值．
【单选题】They said goodbye, little knowing that they were never again. [ ]
A.
met
B.
meeting
C.
to meet
D.
to be met
【多选题】Situation: Jim asked Magid to come into his home. They talked about what they had been doing since Magid left the company. Magid stayed about three hours and then said, "I'd better go now." Jim got up...
A.
Jim thought that Magid should have stayed longer. Three hours was too short for a visit.
B.
Jim thought that Magid should have apologized for visiting without calling first.
C.
Jim thought that Magid had stayed too long and that he should have said something like,“I'm sorry if I've disturbed."
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