feifei 21[求助]

Energy

21. Historian: We can learn about the medical history of individuals through chemical analysis of their hair. It is likely, for example, that Isaac Newton’s psychological problems were due to mercury poisoning; traces of mercury were found in his hair. Analysis is now being done on a lock of Beethoven’s hair. Although no convincing argument has shown that Beethoven ever had a venereal disease, some people hypothesize that venereal disease caused his deafness. Since mercury was commonly ingested in Beethoven’s time to treat venereal disease, if researchers find a trace of mercury in his hair, we can conclude that this hypothesis is correct.
Which one of the following is an assumption on which the historian’s argument depends?
(A) None of the mercury introduced into the body can be eliminated.
(B) Some people in Beethoven’s time did not ingest mercury.
(C) Mercury is an effective treatment for venereal disease.
(D) Mercury poisoning can cause deafness in people with venereal disease.
(E) Beethoven suffered from psychological problems of the same severity as Newton’s.

Energy

12. The only physical factor preventing a human journey to Mars has been weight. Carrying enough fuel to propel a conventional spacecraft to Mars and back would make even the lightest craft too heavy to be launched from Earth. A device has recently been invented, however, that allows an otherwise conventional spacecraft to refill the craft’s fuel tanks with fuel manufactured from the Martian atmosphere for the return trip. Therefore, it is possible for people to go to Mars in a spacecraft that carries this device and then return.
Which one of the following is an assumption on which the argument depends?
(A) The amount of fuel needed for a spacecraft to return from Mars is the same as the amount of fuel needed to travel from Earth to Mars.
(B) The fuel manufactured from the Martian atmosphere would not differ in composition from the fuel used to travel to Mars.
(C) The device for manufacturing fuel from the Martian atmosphere would not take up any of the spaceship crew’s living space.
(D) A conventional spacecraft equipped with the device would not be appreciably more expensive to construct than current spacecraft typically are.
(E) The device for manufacturing fuel for the return to Earth weighs less than the tanks of fuel that a conventional spacecraft would otherwise need to carry from Earth for the return trip.

Energy

21.题好像A好

snow_mountain

12 题。 我选E。 不知道对不对。
21.题。 B。 前不久刚有人问过。search 一下吧。

八戒

以下是引用Energy在2003-12-22 16:52:00的发言：
21.题好像A好

我觉得是B好。

因为没有证据表明：Beethoven ever had a venereal disease

而在当时：mercury was commonly ingested in Beethoven’s time to treat venereal disease。

hiddern assumption:只要有mercury就能推出Beethoven同学有a venereal disease。

而B 排除了他因。
如果B取非的话，就明显说明，即使发现mercury不不能推出Beethoven同学有a venereal disease。

讨论.......

[此贴子已经被作者于2003-12-22 17:36:29编辑过]

JerryGuan

http://forum.chasedream.com/dispbbs.asp?boardid=24&id=7049&star=1#356377


求教

weiyu

--        作者：Energy
--        发布时间：2003-12-21 22:22:00

--        
12.    The    only    physical    factor    preventing    a    human    journey    to    Mars    has    been    weight.    Carrying    enough    fuel    to    propel    a    conventional    spacecraft    to    Mars    and    back    would    make    even    the    lightest    craft    too    heavy    to    be    launched    from    Earth.    A    device    has    recently    been    invented,    however,    that    allows    an    otherwise    conventional    spacecraft    to    refill    the    craft’s    fuel    tanks    with    fuel    manufactured    from    the    Martian    atmosphere    for    the    return    trip.    Therefore,    it    is    possible    for    people    to    go    to    Mars    in    a    spacecraft    that    carries    this    device    and    then    return.    
Which    one    of    the    following    is    an    assumption    on    which    the    argument    depends?    
(A)    The    amount    of    fuel    needed    for    a    spacecraft    to    return    from    Mars    is    the    same    as    the    amount    of    fuel    needed    to    travel    from    Earth    to    Mars.    
(B)    The    fuel    manufactured    from    the    Martian    atmosphere    would    not    differ    in    composition    from    the    fuel    used    to    travel    to    Mars.    
(C)    The    device    for    manufacturing    fuel    from    the    Martian    atmosphere    would    not    take    up    any    of    the    spaceship    crew’s    living    space.    
(D)    A    conventional    spacecraft    equipped    with    the    device    would    not    be    appreciably    more    expensive    to    construct    than    current    spacecraft    typically    are.    
(E)    The    device    for    manufacturing    fuel    for    the    return    to    Earth    weighs    less    than    the    tanks    of    fuel    that    a    conventional    spacecraft    would    otherwise    need    to    carry    from    Earth    for    the    return    trip.    



我选B; E不对,因为说less有问题,是加油后的总重量,不是单独的tank重量. 但是如果两种能源的组成不同,就能说明问题了.

JerryGuan

12题：


题目：因为不能带来回的油料会超重，发不上天；但是只带去的油可以发上天，另外还可以用一个device来使之在空中加油。还因为（%￥#·），所以人类去火星再回来有希望了。


（%￥#·）= device的重量要小于回来的油料，否则就发不上天了。


其实，我在想：给回来的飞船注油的那飞船也没有办法携带回来的油，那它是不是只能被抛弃呢？

snow_mountain

以下是引用weiyu在2004-3-26 21:01:00的发言：
--        作者：Energy
--        发布时间：2003-12-21 22:22:00

--        
12.    The    only    physical    factor    preventing    a    human    journey    to    Mars    has    been    weight.    Carrying    enough    fuel    to    propel    a    conventional    spacecraft    to    Mars    and    back    would    make    even    the    lightest    craft    too    heavy    to    be    launched    from    Earth.    A    device    has    recently    been    invented,    however,    that    allows    an    otherwise    conventional    spacecraft    to    refill    the    craft’s    fuel    tanks    with    fuel    manufactured    from    the    Martian    atmosphere    for    the    return    trip.    Therefore,    it    is    possible    for    people    to    go    to    Mars    in    a    spacecraft    that    carries    this    device    and    then    return.    
Which    one    of    the    following    is    an    assumption    on    which    the    argument    depends?    
(A)    The    amount    of    fuel    needed    for    a    spacecraft    to    return    from    Mars    is    the    same    as    the    amount    of    fuel    needed    to    travel    from    Earth    to    Mars.    
(B)    The    fuel    manufactured    from    the    Martian    atmosphere    would    not    differ    in    composition    from    the    fuel    used    to    travel    to    Mars.    
(C)    The    device    for    manufacturing    fuel    from    the    Martian    atmosphere    would    not    take    up    any    of    the    spaceship    crew’s    living    space.    
(D)    A    conventional    spacecraft    equipped    with    the    device    would    not    be    appreciably    more    expensive    to    construct    than    current    spacecraft    typically    are.    
(E)    The    device    for    manufacturing    fuel    for    the    return    to    Earth    weighs    less    than    the    tanks    of    fuel    that    a    conventional    spacecraft    would    otherwise    need    to    carry    from    Earth    for    the    return    trip.    




我选B; E不对,因为说less有问题,是加油后的总重量,不是单独的tank重量. 但是如果两种能源的组成不同,就能说明问题了.

还是认为E对。weiyu,你的前半句话我没看明白。但是后半句话有问题。文章第一句话就说“The    only    physical    factor    preventing    a    human    journey    to    Mars    has    been    weight.    ”所以组成的问题在这里是out of scope.

weiyu

bryony: 对不起, 没写清楚.



原文说唯一的因素是重量问题:


带上来回的油太重, 不能发射, 所以改带一种加油设备.


E. 加油设备重量<油的重量 (是假设). 谢谢.


但是B说:新产生的油的成分和原来的油一样. 取非后感觉有weaken的意思. 但是没有E来的直接. 结论是it    is    possible    for    people    to    go    to    Mars    in    a    spacecraft    that    carries    this    device    and    then    return.


这里要return, 而且加油是在M大气存在的地方完成的. 所以油的成分如果不同,但是不可以保证其载重量不超出原来的载重量,    也许return有问题?? 但ETS只考必要条件.


在此题中, E是最好的选项, 说明了发射的可能性. 但是并不能保证return. (但ETS只考必要条件. ). 请问高NN, 这里的B这个必要条件怎么理解?

[此贴子已经被作者于2004-3-28 11:50:36编辑过]