要引用当前对象的直接容器对象，应使用A．Parent B．This C．ThisFo

《老人与海》作品采用的是符号阵矩的方法写作的。

下列哪种细胞可产生基质：

A．成纤维细胞

B．黑色素细胞

C．朗格罕细胞

D．组织细胞

E．肥大细胞

Shanghai:       Car rentals（出租） are becoming more and more popular as an inexpensive way of taking to the roads. Business people, foreigners and families alike are making good use of the growing industry.

The first car rental firm opened in Shanghai in 1992 and now 12 car rental players are in the game, with more than 11,500 cars in their books.

The largest player - Shanghai Bashi Tourism Car Rental Center offers a wide variety of choices - deluxe sedans, minivans, station wagons, coaches. Santana sedans are the big favorite.

Firms can attract enough customers for 70 percent of their cars every month. This figure shoots up during holiday seasons like National Day, Labor Day and New Year's Day, with some recording 100 percent rental.

The major market force rests in the growing population of white-collar employees （白领雇员）, who can afford the new service, said Zhuang Yu, marketing manager of Shanghai Angel Car Rental Co.

56. The words "deluxe sedans, minivans" and "station wagons" used in the text refer to ______.

A. cars in the making     B. car rental firms       C. cars for rent          D. car makers

57. Which of the following statements is true according to the text?

A.70% of the cars can be rented out on holiday.

B. 70% of the customers are white-collar employees.

C. More firms are open for service during holiday seasons.

D. Some firms rent out all their cars during holiday seasons.

58. Shanghai's car rental industry is growing so fast mainly due to ______.

A. better cars supplied by producer

B. fast service offered by car rental firms

C. the increasing number of white-collar employees

D. People's growing interest in travelling during holidays

铁、碳素钢、合金钢属于常用工程材料中的（）。

A．黑色金属

B．耐火材料

C．有色金属

D．耐火隔热材料

#jGT#k表示（）。

A.与

B.非

C.大于

D.加