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[Reading Comprehension]

试题详情

文章:

    In addition to conventional galaxies, the universe contains very dim galaxies that until recently went unnoticed by astronomers. Possibly as numerous as conventional galaxies, these galaxies have the same general shape and even the same approximate number of stars as a common type of conventional galaxy, the spiral, but tend to be much larger. Because these galaxies' mass is spread out over larger areas, they have far fewer stars per unit volume than do conventional galaxies. Apparently these low-surface-brightness galaxies, as they are called, take much longer than conventional galaxies to condense their primordial gas and convert it to stars—that is, they evolve much more slowly.

    These galaxies may constitute an answer to the longstanding puzzle of the missing baryonic mass in the universe. Baryons—subatomic particles that are generally protons or neutrons—are the source of stellar, and therefore galactic, luminosity, and so their numbers can be estimated based on how luminous galaxies are. However, the amount of helium in the universe, as measured by spectroscopy, suggests that there are far more baryons in the universe than estimates based on galactic luminosity indicate. Astronomers have long speculated that the missing baryonic mass might eventually be discovered in intergalactic space or as some large population of galaxies that are difficult to detect.

题目:

It can be inferred from the passage that which of the following is an accurate physical description of typical low-surface-brightness galaxies?

选项:

A、They are large spiral galaxies containing fewer stars than do conventional galaxies.
B、They are compact but very dim spiral galaxies.
C、They are diffuse spiral galaxies that occupy a large volume of space.
D、They are small, young spiral galaxies that contain a high proportion of primordial gas.
E、They are large, dense spirals with low luminosity.

答案:

C

提问:

AC比

解答:

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阅读1177
解答: sysadmin

提问:

这题定位啥的都不难,在第一段中后半部分。很轻松选了A。。。。但是答案C。求解释!

解答:

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阅读1199
解答: sysadmin老师

提问:

通过原文low-surface-brightness 这句定位到 Apparently these low-surface-brightness galaxies 那句 接下来就看选项了,选了A

解答:

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阅读1198
解答: sysadmin老师

提问:

听了录音,说杀A是因为没有提到有fewer star,但是我觉得一段的2、3、4句中有说过相应内容且对应,所以还是不明白为什么C比A好。

解答:

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阅读1179
解答: sysadmin老师

提问:

AC比

解答:

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阅读1178
解答: sysadmin老师

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