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问题 单项选择题

某设备目前实际价值为30000元。有关数据见下表：

则在静态模式下，该设备的经济寿命还剩余（）年。

A．1

B．2

C．3

D．4

答案

参考答案：D

解析：

静态模式下设备经济寿命的确定方法，就是在不考虑资金时间价值的基础上计算设备年平均成本为最小的N。就是设备的经济寿命。

式中 CN——N年内设备的年平均使用成本；

P——设备目前实际价值；

Ct——第t年的设备经营成本；

LN——第N年末的设备净残值。

经济寿命

填空题


A Sports体育运动
Many animals engage in play，but homo sapiens is the only animal (1) have invented sports.Since sports are an invention，a part of culture (2) than an aspect of nature，all definitions of sports are somewhat arbitrary. (3) sports are a human universal found in every known culture or a (4) unique to modern society depends upon one’s definition of sports.Men and (5) have always run，jumped，climbed，lifted，thrown， and wrestled，but they have (6) always performed these physical activities competitively. Although all literate societies seem to (7) contests of one sort or another in which men， and sometimes women， (8) in displays and tests of physical skill and prowess，sports may be (9) defined as physical contests performed for their own sake and not for (10) ulterior end.According to this strict definition，neither Neolithic hunters nor contestants (11) religious ceremonies such as the ancient Olympic Games were engaged in sports. (12) on the stipulation that sports must be performed for their own sake (13) the paradoxical elimination of many activities which are usually thought of as (14) ，such as exercises done for the sake of cardiovascular fitness，races run (15) satisfy a physical education requirement，ball games played to earn a paycheck. (16) definition also means abandonment of the traditional usage in which"sport，"derived (17) Middle English disporter，refers to any light hearted recreational activity.In the. (18) of some 18th- century aristocrats，a game of backgammon and the seduction of (19) milkmaid were both considered good sport，but this usage of the term (20) become archaic.

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单项选择题

诊断尿路感染，下列哪项最有意义

A．发热、腰痛、白细胞升高

B．尿频、尿急、尿痛

C．尿沉渣白细胞大于5／HP

D．中段尿培养菌落计数大于105／ml

E．尿亚硝酸盐还原试验阳性
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