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问题 填空题
已知二次函数y＝ax2＋bx＋c中，函数y与自变量x的部分对应值如下
表：
x
…
－4
－3
－2
－1
0
…
y
…
3
－2
－5
－6
－5
…
则x＜－2时， y的取值范围是     ▲    ．
答案

y＞－5

根据图表知二次函数的顶点坐标是（-1，-6），可将二次函数的解析式设为顶点式，任取一点坐标代入即可求得二次函数的解析式，然后根据二次函数的性质填空．

解：由图表知，二次函数的顶点坐标是（-1，-6），

可设二次函数的解析式为：y=a（x+1）2-6；

∵二次函数经过点（0，-5），

∴-5=a-6，

解得，a=1，

∴二次函数的解析式为：y=（x+1）2-6；

∴当x＜-2时，y＞-5；

故答案为：y＞-5．

单项选择题

要使白云突出应用（）滤色镜。

A、ND

B、UV

C、SL

D、黄色
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Questions


·Read the following passage and answer questions.
1. If sustainable competitive advantage depends on work-force skills, American firms have a problem. Human-resource management is not traditionally seen as a central to the competitive survival of the firm of the United States. Skill acquisition is considered an individual responsibility. Labor is simply another factor of production to rent at the lowest possible cost — as much as one buys row materials or equipment.
2. The lack of the importance attached to human-resource management can be seen in the cooperation hierarchy. In an American firm the chief financial officer is almost always second in command. The post of head of human-resource management is usually a specialized job, off at edge of corporate hierarchy. The executive who holds it is never consulted on major strategic decisions and has no chance to move up to Chief Executive Officer. By way of contrast, in Japan the head of human-resource management is central—usually the second most important executive, after the CEO, in the firm’s hierarchy.
3. While American firms often talk about the vast amounts spent on training their work forces, in fact they invest less in the skills of their employees than do either Japanese or German firms. The money they do is also more highly concentrated on professional and managerial employees. And the limited investments on modem training workers are much more narrowly focused on the specific skills necessary to do the next job rather than on the basic background skills that make it possible to absorb new technologies.
4. As a result, problems emerge when new breakthrough technologies arrived. If American workers, for example, take much longer to learn how to operate new flexible manufacturing stations than workers in Germany do (as they do), the effective cost of those stations is lower in Germany than it is in United States. More times is required before equipment is up and running at capacity, and the need for extensive retraining generates costs and creates bottlenecks that limit the speed, with which new equipment can be employed.
5. The result is a slower pace of technological changes. And in the end the skills of the bottom half of the population affect the wages of the top half. If the bottom half cannot effectively staff the processes that have to operated, the management and professional jobs that go with these processes will disappear.

Questions


·For questions, choose the best title for each paragraph from below.
·For each numbered paragraph, mark one letter (A-G) on the Answer Sheet.
·Do not mark any letter twice.
A. The bad effect of poor management on new technologies.
B. The position of human-resource management in corporation hierarchy.
C. The work force — training in American firms.
D. Human-resource management is not important for American firms.
E. How to make American firms become more completive.
F. The importance of worker’s skill.
G. Problems exit in American’s companies.

Paragraph 1: ______
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