下列属于一个DBMS的用户界面应具有的性质是  Ⅰ.可靠性  Ⅱ.易用性  Ⅲ.多样

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问题:

下列属于一个DBMS的用户界面应具有的性质是
  Ⅰ.可靠性  Ⅱ.易用性  Ⅲ.多样性  Ⅳ.立即反馈

A.Ⅰ,Ⅱ和Ⅳ

B.Ⅰ,Ⅱ和Ⅲ

C.Ⅰ,Ⅲ和Ⅳ

D.全部

考点:计算机等级考试数据库技术三级数据库技术笔试
题型:单项选择题

某导体10秒内通过横截面的电荷量为3库,电流做功18焦,通过该导体的电流为______安,导体两端的电压为______伏,导体的电阻为______欧.当导体两端的电压为12伏时,它的电阻为______欧.

题型:单项选择题
When most people think of giant pandas, the pictures of the cute, black-and-white bears from China that eat bamboo will immediately jump into their mind. Scientists from Mississippi State University, however, are interested in what they leave behind: their poop(排泄物). At a recent meeting in Denver, Professor Brown at the university presented her research showing how panda poop could inspire a new way to obtain energy from plants, which are a renewable energy source. Usually, plants can be called biomass(有机燃料) when they are used as an energy source.
Burning biomass is one way to capture its energy, but Brown hopes panda poop can teach scientists something about breaking down biomass. Pandas—or at least the bacteria in their stomachs—are very good at getting energy out of bamboo. Unlike cows, which use 4 stomachs to digest large amounts of grass, a panda has only one stomach. Bamboo comes in, and poop goes out.
Every day for 14 months, Brown and her team on this project, counted the bacteria in the poop of the two pandas, YaYa and LeLe living at the Memphis Zoo. Her studies turned up 12 species of bacteria that break down biomass, including one that had never been found in pandas. Brown says that because the poop contains bacteria that break down biomass, it could also be used to break down other types of biomass.
Now the scientists hope to identify the chemicals that help with the process of breaking down biomass and then figure out how the bacteria work. If those chemicals can be made in the lab, they could be used to turn biomass—like grass or other plants—into fuel.
Brown says she doesn’t mind handling panda poop. “It’s probably the most pleasant material to work with,” she says, “My colleagues and I have been working with other poop for a long time, and we can assure you it has a fairly pleasant smell associated with it.”
小题1:The importance of studying panda poop is _______.
A.to create a renewable energy from plants
B.to explore a new way to get energy from plants
C.to learn a lesson of energy from panda poop
D.to figure out how the bacteria work for us mankind
小题2:The process of the panda poop project can be described as ______.
a. Identify the chemicals helpful to break down biomass.
b. Find the bacteria in panda poop which break down bamboo.
c. Reproduce the chemicals in the lab to turn biomass into energy.
d. Analyze how the bacteria in panda poop work in panda’s stomach.
A. a, b, d, c          B. a, d, c, b          C. b, a, d, c          D. b, d, a, c
小题3:What does the author mainly want to express in the 2nd paragraph?
A.Pandas don’t digest bamboo the same way as cows.
B.Pandas are capable of getting energy using stomachs.
C.Pandas can get energy from bamboo more efficiently.
D.Scientists have learnt something new from panda poop.
小题4:What does Professor Brown think of working with panda poop?
A.SickB.ChallengingC.InspiringD.Enjoyable
题型:单项选择题

7岁男孩,来院检查。测量项目结果如下。

如果要拍摄X线片,下列部位哪一处为首先选择

A.头部

B.膝关节

C.腕及手部

D.足

E.肩关节

题型:单项选择题

集装箱船舶积载图中,箱位如何表示?什么是行位图、汇总清单?

题型:单项选择题

利用兆欧表测量绝缘电阻时,应将G端子()

A.接地

B.接测试点

C.接泄漏电流经过的表面

D.任意接一端

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