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听力原文: The origin of Earth's moon, the largest moon in the solar system, is still something of a mystery. There are some theories about its origin however. Now, keep in mind that a theory of the moon's origin has to be consistent with two important facts. The first fact is that the Earth contains a lot of iron. Most of it has an iron core. But the moon contains practically no iron. The second fact is that other than the difference in iron content, the moon and Earth are composed of accentually the same minerals, a similarity not shared with any other planet or moon in our solar system. One of the earliest theories of the moon's origin, I called it the Capture Theory, proposes that the moon was somehow captured by Earth's gravitational force. This theory is improbable, however, because it assumes that the moon and Earth formed in different parts of the solar system. If this was tree you would expect the moon's composition to be much different from Earth's composition, just as all the other planets in the solar system are so different from Earth. A second theory of the moon's origin is more promising. It is sometimes referred to as the Mars Theory, because according to this theory, when Earth was still molten, it was struck by a planet about the size of Mars. The impact caused the cores of the two planets to melt together and chunks of Earth's crust to be thrown out into space. These chunks came together to form. the moon. Now, member, Earth's crust is low in iron, because the iron is in Earth's core, but high in various other minerals. This then accounts for why there is little iron but lots of other minerals on the moon. (33)
A.
In a geography class.
B.
In an astronomy class.
C.
In a geology class.
D.
In a biology class.
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【多选题】下列对携带动物入境的有关规定,正确的有(    )。
A.
《中华人民共和国禁止携带、邮寄入境的动物、动物产品和其他检疫名录》包括饲养、野生的活动物有三十余种
B.
携带名录以外的动物入境的,作退回或者销毁处理
C.
携带名录以外的动物入境的,必须持有输出动物的国家或者地区政府检验检疫机构出具的检疫证书,入境时向海关申报接受出入境检验检疫机构检疫,经检疫合格后放行
D.
经过国家出入境检验检疫局特许批准,并具有输出国或地区官方出具的检疫证书的动物,不受禁止名录的限制
【简答题】以下物品出境,须向检验检疫机构申报的有( )。[2005年第一次考试真题]
【简答题】假设MC、MP、AVC、AC分别表示边际成本、边际产量、平均可变成本、平均成本,MC曲线达到最低点时,则( )。
【简答题】在一个密闭的房间里,有人建议用正在工作的电冰箱降低室内平均温度,下面哪种做法正确?1、拔掉电源,打开冰箱的所有门;2、保持电源接通,只打开冰箱冷藏室的门;3、保持电源接通,只打开冰箱冷冻室的门;4、保持电源接通,打开冰箱的所有门。(说明,只需在答案处填入选项序号,如:认为选项2正确,只需在答案处,填入数字:2)
【单选题】拧紧螺母时,可以直接将螺母拧紧么?( )
A.
可以
B.
不可以,需先预紧3-5圈
C.
只要不打歪,就可以直接拧紧
【单选题】假设MC、MP、AVC、AC分别表示边际成本、边际产量、平均可变成本、平均成本,MC曲线达到最低点时,则( )。
A.
MC最大
B.
MP最小
C.
AVC最小
D.
AC最小
【单选题】在一个密闭的房间里,有人建议用正在工作的电冰箱降低室内平均温度,下面哪种做法正确?
A.
拔掉电源,打开冰箱的所有门
B.
保持电源接通,只打开冰箱冷藏室的门
C.
保持电源接通,只打开冰箱冷冻室的门
D.
保持电源接通,打开冰箱的所有门
【简答题】在一个密闭的房间里,有人建议用正在工作的电冰箱降低室内平均温度,下面哪种做法正确?1、拔掉电源,打开冰箱的所有门;2、保持电源接通,只打开冰箱冷藏室的门;3、保持电源接通,只打开冰箱冷冻室的门;4、保持电源接通,打开冰箱的所有门。(说明,只需在答案处填入选项序号,如:认为选项2正确,只需在答案处,填入数字:2)
【多选题】以下物品出境,须向检验检疫机构申报的有()
A.
参加巴黎国际时装展览的服装
B.
援助印度洋海啸受灾国家的物资
C.
出境旅客携带的宠物犬
D.
赴欧洲巡演杂技团携带的演艺物品
【多选题】为了防止旅游者走失事故的发生,导游员的正确做法有
A.
多做提醒工作
B.
做好预报工作
C.
尽量不让旅游者单独活动
D.
地陪、全陪、领队应密切配合
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