口岸通关转异地的入境货物到达目的地后，需与目的地检验检疫机构联系检验检疫。 ( )

在时间线上放置的相互叠加的多个音轨声音会产生什么效果如果希望一个轨道的声音在一段时间内听不见，该如何设置必要时画出图形表示。

The United States economy has dipped into economic recession (经济衰退). This caused discomfort and hardship in every level of society; but for many of the nation’s poor, discomfort and hardship turned into misery (苦难).

An increase in homelessness is probably the worst result of a nation’s financial disaster. About 3 million Americans were homeless because of a lack of affordable housing. Experts suggest that a family should spend no more than 30 percent of its income on housing. In fact, in some families housing costs make up 50 percent or more. An unexpected event, such as losing work or illness, can quickly push a family into homelessness.

An article in Time magazine tells a story of one such family. A young couple and their three children rented a two-bedroom apartment for about $350 a month. They could hardly go on with the husband’s $920-a-month take-home pay; so when their rent was raised to $500 a month, they could no longer make ends meet.

Another woman was found dead on a street in Washington D.C., the capital, and she died at a bus-stop across the street from the US Department of Housing and Urban Development.

People become homeless for different reasons. Some may not be able to pay for housing, because they have lost their job and cannot find another place they can afford. Others have mental diseases, or are addicted to drugs or alcohol, many of whom do not live with their family. And what’s more, there are not enough centers for shelter as the government doesn’t pay enough attention to this social problem. 

People are making efforts to solve the problem. However, it will not be easy, because it is a personal and economical problem as well as a social problem.

小题1:The passage is mainly about __________ in the US.

A．ways of solving economic problems

B．homeless people being taken good care of

C．different reasons for economic recession

D．economic recession leading to social problems小题2:In the passage the author supported his view by __________.

A．presenting specific figures

B．giving examples

C．explaining in details

D．discussing different opinions小题3: One main result that economic recession has led to is __________

A．an increase of living costs

B．more and more deaths

C．an increase of homeless people

D．less centers for poor people小题4:How many reasons why people become homeless are listed in the passage?

A．2.

B．3.

C．4.

D．5.

霍乱弧菌最重要的致病物质是

A．菌毛

B．鞭毛

C．霍乱肠毒素

D．内毒素

E．荚膜

体内含量占体重的（）以下就称为微量元素，必需微量元素有（）种

某城市输水管线长4.28kin，DN1200钢管，管道埋深约5.0m，管线位于城市主干道路的非机动车道上。采用明开槽方法施工，沟槽土质为回填杂土及粉砂土。受交通条件制约，沟槽土方挖运和吊车下管安排在晚10时～次日早6时进行，项目部办理了管线开挖占路手续。现场施工发生如下事件： 　

　事件一、为吊车下管方便，选择夜间时段移动护栏临时占用一条机动车道，受到交通管理部门的处罚。 　

　事件二、挖土机开挖沟槽时发现有一段废弃的旧排水砖沟，约请监理工程师查看后，项目部进行挖除和换填石灰粉煤灰稳定碎石。

　事件三、质量员查验准备焊接的管口时，发现有数个坡口范围存在锈渍。 　

　事件四、钢管吊运到沟槽前，作业队在管道内按间距4m加设木支撑。回填作业在沟槽局部偏窄处，钢管下腋角部位采用木夯夯实。回填完毕发现管道竖向变形50mm。

事件三中对管道施焊的坡口，有关规范有哪些规定？