Oligopoly is characterized by a few sellers offering similar products, whereas monopolistic competition is characterized by many sellers offering differentiated products

A、monopoly.

B、duopoly.

C、monopolistic competition.

D、oligopolistic competition.

There are four basic types of competition in business that form. a continuum from pure competition through monopolistic competition and oligopoly(商品供应垄断)to monopoly. At one end of the continuum, pure competition results when every company has a similar product. Companies that deal in commodities such as wheat or corn are often involved in pure competition. In pure competition, it is often the ease and efficiency of distribution that influences purchase.

In contrast, in monopolistic competition, several companies may compete for the sale of items that may be substituted. The classic example of monopolistic competition is coffee and tea. If the price of one is perceived as too high, consumers may begin to purchase the other. Coupons and other discounts (折扣 ) are often used as part of a marketing strategy to influence sales.

Oligopoly occurs when a few companies dominate the sales of a product or service. For example, only five airline carriers control more than 70 percent of all ticket sales in the United States. In oligopoly, serious competition is not considered desirable because it would result in reduced revenue for every company in the group. Although price wars do occur, in which all companies offer substantial savings to customers, a somewhat similar tendency to raise prices simultaneously is also usual.

Finally, monopoly occurs when only one firm sells the product. Some monopolies have been tolerated for producers of goods and services that have been considered basic or essential, including electricity and water. In these cases, it is government control, rather than competition, that protects and influences sales.

Which of the following would be the best title for the passage?

A．Monopolies

B．The Commodity Market

C．The Competition Continuum

D．The Best Type of Competition

There are four basic types of competition in business that form. a continuum from pure competition through monopolistic competition and oligopoly to monopoly. At one end of the continuum, pure competition results when every company has a similar product. Companies that deal in commodities such as wheat or corn are often involved in pure competition. In pure competition, it is often the ease and efficiency of distribution that influences purchase.

In contrast, in monopolistic competition, several companies may compete for the sale of items that may be substituted. The classic example of monopolistic competition is coffee and tea. If the price of one is perceived as too high, consumers may begin to purchase the other. Coupons and other discounts are often used as part of a marketing strategy to influence sales.

Oligopoly occurs when a few companies dominate the sales of a product or service. For example, only five airline carriers control more than 70 percent of all ticket sales in the United States. In oligopoly, serious competition is not considered desirable because it would result in reduced revenue for every company in the group. Although price wars do occur, in which all companies offer substantial savings to customers a somewhat similar tendency to raise prices simultaneously is also usual.

Finally, monopoly occurs when only one firm sells the product. Some monopolies have been tolerated for producers of goods and services that have been considered basic or essential, including electricity and water. In these eases, it is government control, rather than competition, that protects and influences sales.

Which of the following would be the best title for the passage?

A．Monopolies

B．The Commodity Market

C．The Competition Continuum

D．The Best Type of Competition

There are four basic types of competition in business that form. a continuum from pure competition through monopolistic competition and oligopoly (商品供应垄断) to monopoly. At one end of the continuum, pure competition results when every company has a similar product. Companies that deal in commodities such as wheat or corn are often involved in pure competition. In pure competition, it is often the ease and efficiency of distribution that influences purchase.

In contrast, in monopolistic competition, several companies may compete for the sale of items that may be substituted. The classic example of monopolistic competition is coffee and tea. If the price of one is perceived as too high, consumers may begin to purchase the other. Coupons and other discounts (折扣) are often used as part of a marketing strategy to influence sales.

Oligopoly occurs when a few companies dominate the sales of a product or service. For example, only five airline carriers control more than 70 percent of all ticket sales in the United States. In oligopoly, serious competition is not considered desirable because it would result in reduced revenue for every company in the group. Although price wars do occur, in which all companies offer substantial savings to customers, a somewhat similar tendency to raise prices simultaneously is also usual.

Finally, monopoly occurs when only one firm sells the product. Some monopolies have been tolerated for producers of goods and services that have been considered basic or essential, including electricity and water. In these cases, it is government control, rather than competition, that protects and influences sales.

Which of the following would be the best title for the passage?

A．Monopolies.

B．The Commodity Market.

C．The Competition Continuum.

D．The Best Type of Competition.

Anthropologists commonly distinguish three forms of marriage：monogamy，the marriage of one man to one woman，polygyny，the marriage of one man to two or more women，and polyandry，the marriage of one woman to two or more men．Polygyny and polyandry are often linked under the single term“polygamy”，a marriage of one individual to two or more spouses． Though there are many societies which permit，or even encourage，polygamous marriages，it does not follow，in such societies，that every married individual，or even that a majority of them，has more than one spouse Quite the contrary is true，for in most，if not all，of so—called polygamous societies monogamy is statistically the prevailing form．The reason for this is clear：the proportion of male to female births in any human society is roughly the same，and if this proportion is maintained among the sexually mature，a preponderance of plural marriages means that a considerable number of either men or women must remain unmarried No society can maintain itseIf under such conditions；the emotional stresses would be too great to be survived Accordingly，even where the cultural ideals do not prohibit plural marriages，these may occur on any notable scale only societies where for one reason or another，one sex markedly outnumbers the other．In short，monogamy not only pre vails in most of the world’s societies．either as the only approved form. of marriage or as the only feasible form，but it may also prevail within a polygamous society where，very often，only a minority of the population can actually secure more than one spouse In a polygynous household，the husband must supply a house and garden for each of his wives． The wives live with him in turn，cooking and serving for him during the period of his visit．The first wife takes precedence over the others．Polyandry is much rarer than polygyny．It is often the result of a disproportion in the ratio of men to women． In sum，polygamy is not，as so frequently indicated universally a result of human immorality．It is simply not true，in this aspect of culture as in many others，that people who follow patterns of culture deemed immoral in our society are thereby lacking in morality．Our ideal and compulsorypattern of marriage，which holds that monogamy is the only appropriate form. of marriage，is not shared by all peoples，even by some of those who regularly practice monogamy．In a great many so．cieties，monogamy is only one possible form. of marriage，with polygyny or polyandry as perfectly possible，though less frequent，alternatives．

A marriage between several men and women should be called________．

A．polygyny

B．polyandry

C．monogamy

D．not mentioned

寡头价格(Oligopoly price)

Advantages of zinc polycarboxylate cement include which of the following( )

A．kindness to the pulp

B．10ng working time

C．chemical adhesion to tooth structure

D．All of the above