【单选题】【消耗次数：1】
如果低压开关断开,导致压缩机电磁离合器断电,原因可能是( )。
①
制冷剂过量
②
制冷剂严重不足
③
鼓风机不转
参考答案：
复制
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相关题目
【单选题】
在为制冷系统重新加制冷剂时，系统要先抽真空，是因为
①
防止系统空气中的水分在膨胀阀处结冰
②
为了给系统多加注制冷剂
③
为了将系统中的残余的制冷剂排净
④
为了更容易向系统加入制冷剂
随机题目
【简答题】
如何培养学前儿童记忆的持久性？
【简答题】
简述幼儿记忆发展的特点
【单选题】
学前儿童养成良好的用眼习惯，以下说法正确的是（ ）
①
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②
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③
Normal 0 7.8 磅 0 2 false false false EN-US ZH-CN X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.5pt; mso-bidi-font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:宋体; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-font-kerning:1.0pt;} Normal 0 7.8 磅 0 2 false false false EN-US ZH-CN X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:普通表格; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.5pt; mso-bidi-font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:宋体; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-font-kerning:1.0pt;}只要保持正确的看书姿势，长时间的阅读并不会导致儿童眼睛疲劳
④
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【填空题】
最重要并常用的形态指标是（ ）和（ ）。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/><img class="questionIndex" data-index="2" src="/common/images/question_button/BlankSpace2.gif"/>
【填空题】
（ ）规律：上肢最初只有无意识活动，然后学会大把抓，最后才学会用拇指和指拿细小的物体。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/>
【填空题】
（ ）规律：先学会抬头、转头,然后能翻身、学会坐、站立，最后才会走、跑、跳等复杂动作。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/>
【填空题】
幼儿骨的有机物含量较（ ），无机盐含量相对较（ ），所以幼儿骨的弹性大，柔韧性强，而硬度小，容易弯曲变形，不易骨折,一旦骨折，易发生（ ）现象。<img class="questionIndex" data-index="1" src="/common/images/question_button/BlankSpace1.gif"/><img class="questionIndex" data-index="2" src="/common/images/question_button/BlankSpace2.gif"/><img class="questionIndex" data-index="3" src="/common/images/question_button/BlankSpace3.gif"/>