（）是衡量绩效的基准。A.计划值（PV） B.挣值（EV） C.实际成本（AC. D

古代欧洲人一直将亚里士多德的理论当成真理，牛顿力学体系建立后，也一度被看作绝对权威的理论，相对论出现后，解决了经典力学无法解决的难题。这说明[ ]

A．随着社会不断进步，人们会否定更多的真理

B．社会不断进步，促进社会发展的自然科学理论也不断进步

C．人类永远无法找到真理

D．经典力学体系已经过时，为社会所抛弃

提出“六气致病说”的是

A．扁鹊

B．医和

C．文挚

D．长桑君

E．医缓

关于市场环境安全评价的叙述，正确的一项是( )。

A．调查研究为了保护本国市场，采用反倾销等贸易保护措施和知识产权保护、技术贸易壁垒等手段，对拟建项目相关产业发展设置障碍的情况

B．项目所在国产业受到进口倾销等方式损害，市场份额被进口产品不正当竞争所挤占，产业受到实质损害，可能导致企业停产、倒闭，职工下岗、待业，产业发展受到阻碍，影响到社会再生产良性循环和产业安全的情况

C．对市场准入进行有效控制，避免无序竞争和资源浪费的情况

D．以上都不正确

The central problem of economics is to satisfy the people’s and nation’s wants. The problem we are faced with is that our (1) , here identified as money, are (2) . The only way we can resolve our (3) is to make choices. After looking at our resources, we must examine our list of (4) and identify the things we need (5) , those we can postpone, and (6) we cannot afford. As individuals, we face the central problem involved in economics — deciding just how to allocate our limited resources to provide ourselves with the greatest (7) of our wants.
Nations face the same problem. As a country’s population (8) , the need for more goods and services grows (9) . Resources necessary to production may increase, but there are (10) enough resources to satisfy the total desires of a (11) . Whether the budget meeting is taking place in the family living-room, in the conference room of the corporation (12) of directors, or in the chamber of the House of Representatives in Washington, the basic problem still exists. We need to find (13) of allocating limited resources in order to satisfy unlimited wants.
A short time ago, economists divided goods into two categories, free and economic. The former, like air and water, were in (14) abundance that economists had no concern about (15) of scarcity and what to do about it. Today many of these "free goods" are in (16) very expensive to use. Pollution has made clean air and water expensive for producers who have to filter their waste products, for consumers who ultimately pay for the producers’ extra costs, and (17) tax-payers who pay for the government’s involvement in cleaning the environment.
In the 1990s, almost all goods are (18) . Only by effort and money can they be (19) in the form people wish.
Meeting the needs of people and the demands from resources available leads to the basic activity of production. In trying to (20) unlimited wants from limited economic goods, production leads to new problems in economics.

在Word中，可以将编辑的文本以多种格式保存下来，下列选项中，Word支持的保存格式是（）。

A.doc文件、txt文件、rtl文件

B.文本文件、wps文件、位图文件

C.pic文件、txt文件、书写器文件

D.wri文件、bmp文件、doc文件