在公司发行的股票中，优先股的股利是固定的，不因公司获得巨利而提高，而普通股的股利也是

表示单位质量标记物的放射强度的指标是()

A．放射化学纯度

B．免疫活性

C．比放射性

D．交叉反应率

E．亲和常数

造血干细胞和早期细胞的分化抗原是（）

A.MPO

B.CD13

C.CD34

D.CD41

E.CD3

CT脊柱造影增强法扫描的缺点不正确的是（）。

A.需腰椎穿刺

B.需注射药物

C.延长检查时间

D.图像对比度差

E.可能出现不良反应

Americans have four primary avenues for making friends: at work, at school, through a hobby or a (1) such as volunteer work and discussion group, or through a family or (2) .
In American culture, a job is more than the work that one performs between the hours of 9 a.m. and (3) . Work becomes a major socializing influence. Many young mothers who (4) their jobs to care for small children remark on the loneliness of their new lifestyles because they have lost their forum for (5) .
A great number of American employers recognize business social (6) and use it to build a family atmosphere on the job so that employees will feel (7) in their work environment. Some employers arrange company get-togethers in their home or at a (8) . American companies have at least one (9) annually, usually at Christmas time. Many corporations have (10) where employees and administrators alike dress (11) to play games such as baseball and volleyball.
Top American administrators often hold social gatherings (12) . Depending upon the size of the employer’s home and the number of (13) . These social gatherings may be picnics, pool parties, or (14) . If the company is large, an employer may hold what Americans call (15) . For an open house, the employer will invite his employees to come to his home (16) between 1 p.m. on a certain day. Those invited usually stay for (17) , chatting with the other guests and their host. People come and go (18) during the designated hours, and the host keeps refreshments, usually (19) or hors d’oeuvres and beverages, available for all who come. For such social gatherings, it is considered (20) the invitation unless you have an excellent reason.

就两个市场发展来看，（）方式仍占我国科技企业资本市场融资的绝大部分。

A.债券融资

B.股权融资

C.期权融资

D.民间融资