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【单选题】
请根据短文的内容,回答题。 Computer Mouse The basic computer mouse is an amazingly clever invention with a relatively simple design that allows us to point at things on the computer and it is very productive. Think of all the things you can do with a mouse like selecting text for copying and pasting, drawing, and even scrolling on the page with the newer mice with the wheel. Most of us use the computer mouse daily without stopping to think how it works until it gets dirty and we have to learn how to clean it. We learn to point at things before we learn to speak, so the mouse is a very natural pointing device. Other computer pointing devices include light pens, graphics tablets and touch screens, but the mouse is still our workhorse. The computer mouse was invented in 1964 by Douglas Engle hart of Stanford University. As computer screens became more popular and arrow keys were used to move around a body of text, it became clear that a pointing device that allowed easier motion through the text and even selection of text would be very useful. The introduction of the mouse, with the Apple Lisa computer in 1983,really started the computer public on the road to relying on the mouse for routine computer tasks. How does the mouse work? We have to start at the bottom, so think upside down for now. It all starts with the mouse ball. As the mouse ball in the bottom of the mouse rolls over the mouse pad, it presses against and turns two shafts. The shafts are connected to wheels with several small holes in them. The wheels have a pair of small electronic light-emitting devices called light-emitting diodes (LED) mounted on either side. One LED sends a light beam to the LED on the other side. As the wheels spin and a hole rotates by, the light beam gets through to the LED on the other side. But a moment later the light beam is blocked until the next hole is in place. The LED detects a changing pattern of light, converts the pattern into an electronic signal, and sends the signal to the computer through wires in a cable that goes out of the mouse body. This cable is the tail that helps give the mouse its name. The computer interprets the signal to tell it where to position the cursor on the computer screen. So far we have only discussed the basic computer mouse that most of you probably have or have used. One problem with this design is that the mouse gets dirty as the ball rolls over the surface and picks up dirt. Eventually you have to clean your mouse. The newer optical mice avoid this problem by having no moving parts. Most computer users want to know how the computer mouse works. 查看材料
A.
Right
B.
Wrong
C.
Not mentioned
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【多选题】维生素D缺乏性手足搐搦症的惊厥有以下哪些特点()
A.
突然发作,持续数秒、数分
B.
1天发作数次或数天发作1次
C.
发作时意识丧失
D.
醒后活泼如常
E.
同时伴发热
【多选题】可以用于反映企业发展能力的财务指标包括( )。
A.
资产增长率
B.
销售增长率
C.
净利润增长率
D.
营业利润增长率
【多选题】可以用于反映企业发展能力的财务指标包括
A.
资产增长率
B.
收入增长率
C.
资本积累率
D.
净利润增长率
E.
营业利润增长率
【多选题】可以用于反映企业发展能力的财务指标包括( )
A.
资产增长率
B.
收入增长率
C.
资本积累率
D.
净利润增长率
【单选题】维生素D缺乏性手足搐搦症的惊厥有以下特点,但除外
A.
突然发作,持续数秒数分
B.
一天发作数次或数天发作一次
C.
发作时意识丧失
D.
醒后活泼如常
E.
同时伴发热
【单选题】维生素 D 缺乏性手足搐搦症的惊厥有以下特点,但除外
A.
突然发作,持续数秒数分
B.
1 天发作数次或数天发作 1 次
C.
发作时意识丧失
D.
醒后活泼如常
E.
同时伴发热
【多选题】可以用于反映企业增长能力的财务指标包括( )。
A.
资产增长率
B.
销售增长率
C.
净利润增长率
D.
资本积累率
【单选题】维生素D缺乏性手足搐搦症的惊厥有以下特点,但除外
A.
同时伴发热
B.
醒后活泼如常
C.
发作时意识丧失
D.
突然发作,持续数秒至数分钟
E.
1日发作数次或数日发作1次
【单选题】( )全面负责工程的质量、进度、成本、机具、人员的安排调配,是施工工地安全生产、防火、防盗的第一责任人。协调工地各方的关系,代表单位全面处理、办理工程的变更签证。
A.
总经理
B.
项目管理
C.
工程师
D.
施工主管
【多选题】可以用于反映企业发展能力的财务指标包括(    )。
A.
资产增长率    
B.
销售增长率
C.
资本积累率    
D.
净利润增长率
E.
营业利润增长率
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