排放污染物的企业事业单位，应当建立环境保护责任制度，明确（）的责任。A、单位负责人

充血性心衰所产生的胸腔积液为（）

A．漏出液 

B．渗出液 

C．脓性胸液 

D．血性胸液 

E．乳糜性胸液

函数y=3x²+6x﹣2的对称轴是（    ），顶点坐标为（    ）．

In the past, American families tended to be quite large. Parents raising five or more children were common. Over the years, the size of the family has decreased. One reason for this is an increase in the cost of living. On the average, children attend schools for more years than they used to, making them financially dependent on their families longer. Moreover, children nowadays are better dressed and have more money to spend on entertainment. The parents usually take the responsibility for all the expenses. Meanwhile, families are less close than they used to be. More and more American mothers work away from home. The break up of the family occurs when the parents divorce. A lot of children in the U. S. live part of their young lives with only one parent. Broken families usually result in problems for children and parents alike. Children blame themselves when their parents separate. They grow up feeling unsettled as they are moved back and forth between parents. Usually one parent is responsible for raising the children. These single parents must care for the children’s emotional and psychological needs while also supporting them financially. This is very demanding and leaves very little time for the parent’s own personal interests. Single parents often marry other single parents. In this type of family, unrelated children are forced to develop brother or sister relationship. The situations of many American families today are not good. However, recent signs indicate that things are getting better. The divorce rate is declining. The rate of childbirth is rising. Perhaps Americans have learned how important families are.

小题1:In the past, American families tended to be ____.

A．quite small

B．medium sized

C．quite large

D．small小题2:To parents who take the responsibility for children’s expenses, the cost of living increases because ____.

A．children attend school for more years

B．children are better dressed

C．children spend more money on entertainment

D．all of the above小题3:According to the author, the situations of American families in the future may ____.

A．become worse

B．remain the same

C．get better

D．keep unchanged小题4:The title of the article might be ____.

A．American Children

B．American Families

C．American Mother

D．American Parents

升级版本时下载所有版本文件都失败，应如何处理？

多发于10岁以下儿童的是（）

A.髋部扭挫伤

B.髋关节暂时性滑膜炎

C.扳机指

D.颈椎病

E.网球肘