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【简答题】
某化学兴趣小组对教材中“测定空气里氧气含量”的实验（见图I）进行了大胆改进，设计图（Ⅱ）（选用容积为45mL的18×180mm的试管作反应容器）实验方案进行，收到了良好的效果．请你对比分析下面图I、图Ⅱ实验，回答下列有关问题： （1）图I实验中红磷燃烧的实验现象是：______， 等A瓶冷却后打开止水夹，现象为：______．变化过程的文字表达式为______．反应基本类型为：______（“化合反应”或“分解反应”） （2）图Ⅱ实验的操作步骤如下：①点燃酒精灯．②撤去酒精灯，待试管冷却后松开弹簧夹．③将少量红磷平装入试管中，将20mL的注射器活塞置于10mL刻度处，并按图Ⅱ中所示的连接方式固定好，再将弹簧夹紧橡皮管．④读取注射器活塞的数据．你认为正确的实验操作顺序是______（填序号）． （3）图Ⅱ实验中，注射器活塞将从10mL刻度处慢慢前移到约为______mL刻度处才停止． （4）对照图I、图Ⅱ实验，图Ⅱ实验的装置有何优点？（回答一点即可）______．
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【单选题】稳压管 D Z 的稳定电压值为 ± U Z ,且 U Z 值小于运放的饱和电压值 U O (sat) ,当 u i =+ U Z 时, u O 的值为 ( ) 。
A.
+ U Z
B.
- U Z
C.
[R1/(R1+R2)]UZ
【单选题】Ethical criteria for judging appropriate conduct define
A.
what is wise based on trying to understand the efficacy of the tactic and the consequences it might have on the relationship with the other.
B.
what a negotiator can actually make happen in a given situation.
C.
what is appropriate as determined by some standard of moral conduct.
D.
what the law defines as acceptable practice.
E.
All of the above are defined by ethical criteria for judging appropriate conduct.
【单选题】判断农田形式是否合理的依据是The basis for judging the reasonable form of farmland is
A.
与列为世界遗产的农田形式一致 consistent with the farmland form listed as a World Heritage
B.
与当地的等高线平行 parallels to the local contour lines
C.
利于大型机械耕作 good for large-scale mechanical farming
D.
利于当地人地和谐 conducive to local harmony
【单选题】( ) is a basic principle for judging the causal relationship between the risk accident and the loss of the subject-matter insured, so as to determine the insurance liability.
A.
The principle of proximate cause
B.
The principle of loss compensation
C.
The principle of subrogation
【单选题】稳压管 D Z 的稳定电压值为± U Z ,且 U Z 值小于运放的饱和电压值 U O (sat) ,当 u i = - U Z 时, u O 的值为 ( ) 。
A.
+ U Z
B.
- U Z
C.
0
【简答题】For judging the ______________, the present is more ______________ than the _____________.
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