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（1）配制溶质的质量分数为20%的氢氧化钠溶液的步骤： ①在天平上称量氢氧化钠固体，②装瓶并贴标签，③溶解，④计算．其正确的顺序为_________（填序号）． （2）若用溶质的质量分数为37%的浓盐酸配制稀盐酸，打开浓盐酸的试剂瓶时，看到试剂瓶口发生的现象是_________． （3）若在20mL溶质的质量分数为37%的浓盐酸（密度为1.18g/cm 3 ）中慢慢注入60mL水配成稀盐酸，则所得稀盐酸中溶质的质量分数的计算式为（水的密度为1.0g/cm 3 ）_________． （4）某化学兴趣小组的同学在实验室配制了溶质的质量分数为10%的氢氧化钠溶液、5%的盐酸和10%的盐酸三种溶液．但他们忘记了给三种溶液贴上标签．他们想对三瓶溶液进行鉴别，老师只给他们提供了无色酚酞试液、试管和胶头滴管．如果你是小组的成员，请用简便的方法鉴别出三种溶液，并完成下列实验报告．
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【单选题】Which of the following is usually not part of a Spatial DBMS
A.
Spatial data types, e.g., points, line-strings, polygons.
B.
Spatial operations, e.g., distance, inside, neighbor.
C.
Spatial data-structures, e.g., R-tree
D.
Spatial algorithms, e.g., tree-matching
E.
Spatial visualization, e.g., fly through
【简答题】In the author's opinion, visual and spatial abilities are good for ______. A) achieving one's objects B) mind and body C) programming talents into the brain D) imagination and communication
【单选题】The spatial distribution of different racial and ethnic populations demonstrates that segregation persists in virtually all of America's housing markets, from large urban areas to rural counties. What...
A.
hypothesizing about a set of circumstances
B.
chronicling the emergence of a phenomenon
C.
comparing two conflicting points of view
D.
cataloging the cause and effects of a phenomenon
E.
arguing the necessity of solving a problem
【简答题】What is Spatial Operations? Write three basic spatial operations.
【简答题】spatial specificity
【简答题】洪深的《农村三部曲》包括独幕剧《_》、三幕剧《_》、四幕剧《_》。
【单选题】The difference between males and females in visual-spatial skills and verbal ability seems to originate ______.
A.
in adulthood
B.
in childhood
C.
from school experiences
D.
from inborn hormonal conditions
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