单项选择题

水电厂设计中，关于低压厂用电系统短路电流计算的表述，下列哪一条是错误的？（ ）

A.应计及电阻
B.采用一级电压供电的低压厂用电变压器的高压侧系统阻抗可忽略不计
C.在计算主配电屏及重要分配电屏母线短路电流时，应在第一周期内计及异步电动机的反馈电流
D.计算0.4kV系统三相短路电流时，回路电压按400V，计算单相短路电流时，回路电压按220V
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Task 2Directions: This task is the same as Task 1. The 5 questions or unfinished statements are numbered 41 through 45.Exercise should play a very large role in our daily lifE.Everyone, no matter what age, needs exercise every day. However, modem life may prevent people from getting the daily exercise they neeD.There are many kinds of exercises that help people keep physically(身体上地) fit, if they axe done every day. There are sit-up(仰卧起坐) exercises that anyone can perform. for a few minutes every day. For a young person football is one of the best games. If more people would exercise daily, they would find themselves better all the timE.Television and other modem inventions could possibly be a factor that produces physical unfitness(不适). Television can be very educational, but mostly it is just a waste of time: With the automobile(汽车), another modem invention, people no longer walk to any placE.If people are going to sit for hours in front of their TV sets and ride in their cars everywhere, they need to get exercise by sit-ups or playing football.Which is the best title for this passage?A.Exercise in Daily LifeB.The Importance of Watching TVC.Sit-up Is the Best SportD.TV Is Better Than Car
A.Exercise
B.
C.
D.
Which
E.Exercise
F.The
G.Sit-up
H.TV
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根据下列文字回答下面问题1996年至2001年，我国高技术产业中“三资”企业数从7千家增加到1万余家，年均增长6.9%，分别比全部“三资”企业和全部高技术产业企业增长速度快2.3和0.3个百分点；从业人员从109万人增加到196万人，年均增长12.4%，分别比全部“三资”企业和全部高技术产业企业增长速度快7和10.5个百分点：营业收入从1 787亿元增加到6 462亿元，占全部高技术产业营业收入增加额的62%。这表明，近几年我国高技术产业中“三资”企业发展迅速，其增长速度明显高于同期全国“三资”企业与全国高技术产业平均增长速度，呈现出快速增长的态势。2001年在我国“三资”高技术产业企业中，电子及通信设备制造业企业约6千家，占59.1%；从业人员132万人，占67.2%；营业收入4 387亿元，占67.9%。可以看出，我国“三资”高技术产业企业主要分布在电子及通信设备制造业，各项指标所占比重均在六成左右。与1996年相比，2001年高技术产业中“三资企业”的从业人员数量增长了( )。A.12.4%B.70%C.80%D.90%
A.9%，分别比全部“三资”企业和全部高技术产业企业增长速度快2.3和0.3个百分点；从业人员从109万人增加到196万人，年均增长12.4%，分别比全部“三资”企业和全部高技术产业企业增长速度快7和10.5个百分点：营业收入从1
B.1%；从业人员132万人，占67.2%；营业收入4
C.9%。可以看出，我国“三资”高技术产业企业主要分布在电子及通信设备制造业，各项指标所占比重均在六成左右。
与1996年相比，2001年高技术产业中“三资企业”的从业人员数量增长了(
D.12.4%
B.70%
C.80%
D.90%
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