题干

大量信息的存储和多用户的使用对信息安全提出了严峻的挑战,下列四项中对计算机系统的信息危害最大的是(  )

A:内存大小

B:计算机病毒

C:电脑的存储速度

D:电脑的计算速度

上一题 下一题 0.0难度 选择题 更新时间:2016-07-04 12:17:51

答案(点此获取答案解析)

B

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完形填空

    I met Mrs. Neidl in the ninth grade on a stage-design team for a play and she was one of the directors. Almost instantly I loved her. She had an unpleasant voice and a direct way of speaking,1 she was encouraging and inspiring. For some reason, she was impressed with my work and Mrs. Neidl would ask me for my 2 .She wanted to know how I thought we should 3 things. At first I had no idea how to answer because I knew 4about stage design! But I slowly began to respond to her 5. It was cause and effect. She believed I had opinions, so I began to 6 them. She trusted me to complete things, so I completed them perfectly. She loved how 7 I was, so I began to show up to paint more and more. She believed in me, so I began to believe in myself.

    Mrs. Neidl's 8 that year was, “Try it. We can always paint over it 9!” I began to take 10. I had been so afraid of failing but suddenly there was no failing---only things to be 11 upon. I leaned to dip my brush into the paint and 12 create something.

    The shy, quiet freshman achieved success that year. I was 13 in the program as “Student Art Assistant” because of the time and effort I'd put in. It was that year that I 14 I wanted to spend the rest of my life doing stage design.

    Being on that stage-design team 15 Mrs. Neidl changed me completely. Not only was I stronger and more competent than I had thought, but I also 16 a strong interest and a word I hadn't known existed. She taught me not to 17what people think I should do. She taught me to take chances and not be 18 Mrs. Neidl was my comforter when I was upset. Her 19 in me has inspired me to do things that I never imagined 20.