某宗房地产预计未来每年的净收益为8万元，收益期限可视为无限年，该类房地产的报酬率为8

证券自营业务是指上市公司以盈利为目的并以自己的资金和账户买卖有价证券的行为。( )

Seventeenth-century houses in colonial(殖民地的) North America were simple structures that were primarily functional, carrying over traditional designs that went back to the Middle Ages. During the first half of the eighteenth century, however, houses began to show a new fashion. As wealth increase, more and more colonies built fine houses.

Since art of constructing houses was not yet a specialized profession in the colonies, the design of buildings was left to carpenters who were responsible for interpreting handbooks relating to the design of houses imported from England. Libraries still preserve an astonishing number of these handbooks for builders, and the houses appeared during the first three-quarters of eighteenth century show their influence. Nevertheless, most of them display a wide difference of taste and freedom of using the rules in these books.

Increasing wealth and growing experience throughout the colonies resulted in houses of improved design, whether the material was wood, stone, or brick. New England still favored wood, though brick houses became common in Boston and other towns, where the danger of fire urged the use of more durable material. A few houses in New England were built of stone, but only in Pennsylvania and neighboring areas were stone widely used in accommodations. An increased use of brick in houses and outbuildings is noticeable in Virginia and Maryland, but wood remained the most popular material even in houses built by wealthy landowners. In the Carolinas, wooden houses were much more common than brick houses.

Eighteenth-century houses showed great interior improvements over what they were before. Windows were made larger and shutters were taken away. Large, clear sheet of glass replaced the small leaded glass of the seventeenth century. Doorways were larger and more decorative. Fireplaces became decorative features of rooms. Walls were made of plaster(灰泥) or wood, sometimes were decorated with square or rectangular wooden boards. White paint began to take the place of blues, yellows, greens and lead colors, which had been popular for walls in the earlier years. After about 1730, advertisements for wallpaper styles in scenic pattern began to appear in colonial newspapers.

51. What does the passage mainly about?

A. The improvement design of eighteenth-century colonial houses.

B. The comparison of eighteenth-century houses and modern ones.

C. The structures of eighteenth –century colonial houses.

D. The roles of carpenters in building eighteenth-century houses.

52. What was one of the main reasons for the change in eighteenth-century houses in North America?

A. More designers arrived in the colonies in North America.

B. The carpenters were smart and experienced enough.

C. Bricks were more widely used in North America.

D. The colonists had more money to spend on housing.

53. According to the passage, who designed houses in eighteenth-century North America?

A. Professional designers.                             B. House owners.

C. Businessmen.                                    D. Carpenters.

54. Where was stone commonly used to build houses?

A. Virginia.               B. Pennsylvania.           C. Boston.             D. Charleston.

55. What does the author imply about the use of wallpaper before 1730?

A. Wallpaper was introduced in handbooks of designing houses.

B. Wallpaper was the same color as what the wall was painted.

C. Patterned wallpaper was not widely used.

D. Wallpaper was not used in stone houses.

(一)材料一：在某市一条不足400米长的步行街上，清洁工人清理出人们吐掉的口香糖约15公斤。某市公交公司无人售票公共汽车3年间收到的残币假钞竟高达50万元。一孕妇在参加公务员录用考试后上了专门接送考生的大客车，全车考生没有一个人给她让座。材料二：在对某市市民社会公德现状的一次调查中，99%的受访者认为不应该随地吐痰，但真正吐到手纸扔到垃圾箱里的不足50%;雨季商店为顾客准备的文明伞，表示用完后及时归还的占受访者的81%，但下雨过后，商店真正回收的雨伞仅占发放的10%;人人皆知本市严重缺水，但公共用水的浪费却十分惊人。

关于社会公德，以下表述正确的有()。

A．是全体公民在社会交往和公共生活中应该遵循的行为准则

B．涵盖了人与人、人与社会、人与自然之间的关系

C．以“文明礼貌、助人为乐、爱护公物、保护环境、遵纪守法”为主要内容

D．是整个社会道德体系的基础

雷诺数Re可用来判别流体的流动状态，当（）时是层流状态。

A.Re小于2300

B.Re大于2300

C.Re大于1000

D.Re小于1000

据统计，我国每年购买图书支出20～100元的人占30%，支出101～200元的人占25%，支出201～300元的人占26%。拥有藏书50～100册的人占50%，拥有藏书100～200册的人占28%。

如果每个人的阅读量是藏书的60%，拥有藏书200册的人有多少册书未阅读______

A．60
B．40
C．80
D．90