金属导体中定向移动形成电流的是______;在酸、碱、盐的水溶液里定向移动形成电

题型:填空题

问题:

金属导体中定向移动形成电流的是______;在酸、碱、盐的水溶液里定向移动形成电流的是______.

考点:导体,绝缘体电流的形成
题型:填空题

下列说法正确的是(  )

A.地壳中含量最多的元素是氧

B.工业制氧气过程的化学变化

C.镁在氧气中比在空气中燃烧剧烈,有耀眼白光,并生成白色固体

D.铁生锈是铁与氧气、二氧化碳、水共同作用的结果

题型:填空题

现实当中,人们的许多活动、做法都跟我们学过的物理知识有关,下列对涉及压强和浮力的事例论述不正确的是[ ]

A.用吸管能把饮料吸人嘴里,其实是大气压强的作用

B.石头扔进河里会沉入水底说明石头在水中不受浮力

C.用高压锅煮食物熟得快是因为锅内气压加大使液体(锅内的水)的沸点升高

 D.拦河坝坝堤筑成上窄下宽是因为液体(坝里的水)的压强随深度增大而增大

题型:填空题

I really love my job because I enjoy working with small children and like the challenges and awards from the job. I also think my work is important. There was a time when I thought that I would never have that sort of career.

I wasn’t an excellent student because I didn’t do much schoolwork. In my final term I started thinking what I might do and found I didn’t have much to offer. I just accepted that I wasn’t the type to have a career.

I then found myself a job, looking after two little girls. It wasn’t too hard at first. But the problems began when I agreed to live in, so that I would be there if my boss had to go out for business in the evening. We agreed that if I had to work extra hours one week, she’d give me time off the next. But unfortunately, it didn’t often work out. I was getting extremely tired and fed up because I had too many late nights and early mornings with the children.

One Sunday, I was in the park with the children and met Megan who used to go to school with me. I told her about my situation. She suggested that I should do a course and get a qualification if I wanted to work with children. I didn’t think I would be accepted because I didn’t take many exams in school. She persuaded me to phone the local college and they were really helpful. My experience counted for a lot and I got a part-time course. I had to leave my job with the family and got work helping out at a kindergarten.

Now I have got a full-time job there. I shall always be thankful to Megan. I wish I had known earlier that you could have a career even if you aren’t top of the class at school.

47. What is the author’s present job?

A. Working part-time in a college.                     B. Taking care of children in a family.

C. Helping children with their schoolwork.  D. Looking after children at a kindergarten.

48. When staying with the two girls’ family, the author _______.

A. was paid for extra work                      B. often worked long hours

C. got much help from her boss             D. took a day off every other week

49. What has the author learned from her own experiences?

A. Less successful students can still have a career.

B. Qualifications are necessary for a career.

C. Hard work makes an excellent student.

D. One must chose the job she likes.

50. What does the underlined sentence probably mean?

A. The boss didn’t go out to work very often.

B. The boss often failed to keep his agreement with the writer.

C. The writer couldn’t go out to find another job.

D. The writer seldom had any chance to work outside.

题型:填空题

以下除锈工序排列正确的是()。

①除去表面各种可见污物;②用钨钢铲刀铲去大面积锈蚀;③锉除去焊渣等突出物和各种毛刺;④刮刀和钢丝刷除去边角部位锈蚀;⑤再用溶剂或清洗剂除油。

A、①②③④⑤

B、①③②④⑤

C、①②⑤④③

D、①⑤②④③

题型:填空题

校车、送餐车等运输路线的设计,属于______。

A.起讫点不同的单一路径规划
B.多个起讫点的路径规划
C.起点与终点相同的路径规划
D.产销平衡的运输问题

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