闭回路是一条封闭折线，每一条边都是（） A.水平 B.垂直 C.水平＋垂直 D.水平

就业是民生之本。回答1~2题。

1．读下图“有人没活干，有活没人干”。这启示我们

①要树立自主择业观 ②要树立竞争就业观 ③要树立职业平等观 ④要树立多种形式就业观

A．①③

B．①④

C．②③

D．②④

2．北京市工商局规定，应届高校毕业生申请登记注册企业，如果自家有四合院、平房等住宅，在提供有关证明文件之后也可将其作为住所（经营场所）直接登记注册，可以利用互联网帮助发布企业登记公告并免收公告费。这表明 [ ]

A．实现就业必须通过市场竞争

B．高校毕业生应人人自主创业

C．政府鼓励高校毕业生自主创业

D．选择职业只能根据个人兴趣专长

由于工艺上的原因，在铸件相应部位非加工面上增加的金属层厚度称为（）。

A.非加工壁厚负余量

B.工艺补正量

C.补贴

D.分型负数

第三部分阅读理解（共两节，满分40分）

第一节（共15小题；每小题2分，满分30分）

　　阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。

A

　　Soon it may be harder to stop and smell the roses.

　　Growing levels of air pollution from power plants and automobiles have reduced flower fragrances (芬芳) by up to 90 percent in the US.That is compared with pre-industrial levels,a new study has found.

　　The trend is unpleasant for human noses,but may be life - threatening for bees and butterflies.

　　"Many insects find flowers by folowing the scent(香味) produced by those flowers," said the studies lead author Jose D.Fuentes,an environmental scientist at the University of Virginia.

　　"The increasing pollution makes it difficult for them to locate the flowers and feed on their nectar(花蜜)."

　　Scientists have alrady known that flowers produce scent molecules(分子) that bond with pollutants.The process breaks down the plants' sweet smell.

　　With more pollution in the air,the scent molecules don't remain effective as long and travel shorter distances on the wind.

　　The new study suggests that in the mid - 19th century,when pollution levels were first recorded,scent molecules would have been able to travel some 1,000 to 1,200 meters.

　　Today,in the polluted air found downwind of large cities,scentst may only make it some 200 to 300 meters.

　　The report was recently published in the journal,Atmospheric Environment.

　　Bee farmers have reported that bee populations are dropping dramatically in many parts of the world in recent years. Could these missing scents be a factor?

　　Scientists trying to hind the cause of bee population declines have blamed bacteria,pesticides,and even cellphone radiation.

　　Jay Evans,an entomologist(昆虫学者) at the US Department of Agriculture's bee research laboratory,was interested in the new study.But he says he hasn't seen bee behavior that suggests trouble with scents.

　　"Over the last couple of summers I don't think the bees in this area were bringing in much less food,"he said.

　　"It might be that they had to work harder,but it seems like as long as there were bees to collect food they were finding flowers somewhere."

　　But Fuentes fears that the fading smell of flowers may stress insects that are already faced with other threats.

　　"The effects shown in these studies will simply exacerbate whatever the bees are going through right now,"he said.

　　"It's something that is really worthwhile paying attention to."

　　56.What's the passage mainly about?

　　　A.How greatly air plooution affects our lives.

　　　B.Effects of air pollution on bee populations.

　　　C.Measures to fight air pollution.

　　　D.The rapid decline of bee populations in the world.

　　57.According to the passage,Jay Evans probably agrees that ______ .

　　　A.bees are the insect that suffers most from air pollution

　　　B.bees are at risk of dying out owing to air pollution

　　　C.the fading smell of flowers doesn't affect bees so greatly as was thought

　　　D.as is often the case,bees fail to locate the flowers because of the missing scents

　　58.The word"exacerbate" in the last paragraph but one probably means ______.

　　　A.worsen B.improve C.get rid of D.decrease

　　59.Which of the following is NOT true according to the passage?

　　　A.The more air pollution there is in a region,the greater the destruction of the flower scents.

　　　B.Bacteria,pesticides,and cellphone radiation are blamed for causing the decline of bees.

　　　C.The scent molecules produced by flowers in a less polluted environment oculd travel longer and farther.

　　　D.Air pollution does more harm to insects such as bees and butterflies than human beings.

棘球蚴在人体最常见的寄生部位是（）

A.肌肉

B.骨

C.肝

D.肺

E.脑

滇重楼的入药部位是（）。