大便隐血试验阳性，说明上消化道出血量约为（） A.＞1ml B.＞5ml C.＞20

阅读下面短文，根据短文回答问题。

    From June 1 this year, plastic bags were no longer free in stores and supermarkets. What do people use

to hold their shopping now? What do they think of the new rule?

   The students of Beijing 101 Middle School did a survey to find the answer. With the help of the Sony

Company, they designed a questionnaire (问卷) and made their own shopping bags. On June 5, the students

gave the bags away to people in the street. Anyone who wanted a free bag had to fill in a questionnaire.

    Li Xuan, 14, one of the students said that most of the people were middle-aged and elderly. They said they

were "optimistic (乐观的)" about the future of shopping bags. But these people also said there was a problem

with getting a bag if you couldn't make one yourself. They said that shopping bags in supermarkets are too

expensive. They said a reasonable price for a shopping bag is about two yuan.

    Zhang Yue, 16, another student, said that people also care about the quality of the shopping bag and how

much it can hold. Young people, however, want their bags to be nice and to look cool. Currently, most

supermarkets' shopping bags only have the store's brand (商标).

1. Can people get free plastic bags in stores and supermarkets now?

2. Who did a survey about the shopping bags?

3. What do people think of the shopping bags in supermarkets now?

4. Besides the price, what else do people care about the shopping bags?

5. What do young people want their bags to be?

处方前记的内容有( )。

A．配方人签名

B．用药方法

C．发药日期

D．临床诊断

E．药品名称

单纯用激光照射牙齿防龋，其功能不包括()

A．釉质表面形成抗酸性强的玻璃样物质

B．减少牙脱钙量

C．促进再矿化

D．抑制变形链球菌的生长

E．以上各项均不包括

进行焊接工作时，必须设有防止金属熔渣飞溅、掉落引起（）的措施以及防止（）、（）、（）等措施。焊接人员离开现场前，必须进行（），现场应无火种留下。

有一个学生关系模式Student，其字段有no(学号)，name(姓名)，age(年龄)，sex(性别)。在这些字段中，最适合作为主键的是( )。

A．no
B．name
C．age D．sex