恶性肿瘤对机体的危害主要体现在（）A.膨胀性生长B.侵袭性生长C.产生过量激素D.压

教育史上两大对立学派--传统教育学派与现代教育学派的代表人物分别是（）。

A.凯洛夫和赫尔巴特

B.赫尔巴特和杜威

C.凯洛夫和杜威

D.夸美纽斯和杜威

患者后项部有一苔藓样的皮损，呈淡褐色片状，粗糙肥厚，剧痒时作，应诊断为（）

A.慢性湿疹

B.白疕

C.牛皮癣

D.风瘙痒

E.癣

无土栽培的优点。

以下关于信息系统集成的描述中，错误的是______。

A．系统集成包括技术、管理和商务等各项工作，管理和商务活动是系统集成工作的核心

B．计算机网络系统集成实现的关键在于解决系统之间的互连和互操作问题

C．应用系统集成又称为行业信息化解决方案集成，独立的应用软件供应商成为其中的核心

D．系统集成的最终交付物是一个完整的系统而不是一个分立的产品

Workforce is defined as the total number of people who are available to work and earn incomes. The definition includes everyone who is employed or seeking paid employment, so it includes employers and the self-employed.

Although the size of the workforce depends a great deal on the size of the total population, there are several other influences which also affect it. The age distribution of the total population has a very marked effect on the available workforce. If the population has a high proportion of very young people or of those too old to work, then the available workforce would be lower than if there were an evenly spread age distribution. If the population grows rapidly from natural increase, i.e., the number of births greatly exceeds the number of deaths, then as the total population increases, the proportion in the workforce declines

Sometimes a population is described as aging, which means that the birth rate is either falling or growing very slowly, and as people retire from the workforce, there are not enough young people entering it to replace those who are leaving it. The population is top-heavy with older people. So the percentage of the population in the workforce declines when there is either a rapid increase in births or a falling birth rate.

The age distribution of the population has several important effects on the economy. If the population is aging and there is an increase in the number of people retiring without a corresponding increase in the number entering the workforce, this raises the problem of the ability of the economy to provide a reasonable level of social services to the retired group. If the aged are to be cared for in special homes or hotels, finances must be available for that purpose. If the size of the workforce is small relative to the total population, then the government tax receipts are relatively low and either the government has less money available to it or the workforce members have to be taxed more heavily.

Workforce is composed of ().

A. both the employed and the self-employed

B. people employed to work for others

C. both employers and employees

D. people available to work and earn incomes