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masya89 [10]
1 year ago
6

Astronomers theorize that a black hole forms when a massive object shrinks catastrophically under its own gravity, leaving only

a gravitational field so strong that nothing escapes it. Astronomers must infer the existence of black holes, which are invisible, from their gravitational influence on the visible bodies surrounding them. For example, observations indicate that gas clouds in galaxy M87 are whirling unusually fast about the galaxy’s center. Most astronomers believe that the large concentration of mass at the galaxy’s center is a black hole whose gravity is causing the gas to whirl. A few skeptics have argued that the concentration of mass necessary to explain the speed of the whirling gas is not necessarily a black hole: the concentration in M87 might be a cluster of a billion or so dim stars. The same hypothesis might have been applied to the galaxy NGC 4258, but the notion of such a cluster’s existing in NGC 4258 was severely undermined when astronomers measured the speed of a ring of dust and gas rotating close to the galaxy’s center. From its speed, they calculated that the core’s density is more than 40 times the density estimated for any other galaxy. If the center of NGC 4258 were a star cluster, the stars would be so closely spaced that collisions between individual stars would have long ago torn the cluster apart.
1. The skeptics mentioned in the first paragraph would be most likely to agree with the astronomers mentioned in line 13 about which of the following statements concerning the galaxy M87?(A) The speed of the gas whirling around the center of M87 is caused by a dense object that is not a black hole.(B) The concentration of mass at the center of M87 is probably a large cluster of dim stars.(C) The presence of a black hole at the center of M87 is the most likely explanation for the speed of the gas whirling about the galaxy’s core.(D) The speed of the gas whirling around the center of M87 is caused by a large concentration of mass at the core of M87.(E) The gravitational influence of a star cluster would not be strong enough to account for the speed of the gas whirling around the core of M87.2. The passage asserts which of the following about the existence of black holes?(A) Astronomers first speculated about the existence of black holes when they observed gas whirling around the center of a particular galaxy.(B) Evidence used to argue for the existence of black holes is indirect, coming from their presumed effects on other astronomical bodies.(C) Recent observations of certain astronomical bodies have offered proof.(D) A considerable body of evidence suggests the existence of black holes, even though their behavior is not completely consistent with the laws of physics.(E) Many astronomers are skeptical about certain recent evidence that has been used to argue for the existence of black holes.3. Which of the following, if true, would most clearly undermine the possible explanation for the whirling gas in M87 that is mentioned in the last sentence of the first paragraph?(A) The stars in a star cluster at the center of M87 could exert a strong gravitational force without tearing the cluster apart.(B) A cluster of stars at the center would preclude the existence of certain other astronomical phenomena that have been observed at the center of M87.(C) The stars within many existing galaxies, such as NGC 4258, are more closely spaced than are the stars within the core of M87.(D) Only one other galaxy has been observed to contain gas clouds whirling about its center as they do about the core of M87.(E) The gravitational force of a cluster of a billion or so dim stars would be sufficient to cause a whirling ring of gas and dust to collect around the center of a galaxy.4. The passage is primarily concerned with(A) explaining why a particular phenomenon is so rare(B) criticizing a method used to gather data about a natural phenomenon(C) considering possible instances of a particular phenomenon(D) distinguishing among several different kinds of natural phenomena(E) questioning a widely accepted explanation for an unusual phenomenon
English
1 answer:
Yanka [14]1 year ago
6 0

Explanation:

The black holes are formed when a sun dies.

The sun blasts and it forms a black hole which is in visible to the naked eye.

When something is pulled inside a black hole, the matter is squeezed.

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In Kafka's story, Gregor was at his job for fifteen years without being ill. However, in the graphic novel, Gregor had not been
horsena [70]

Answer:

From the book and the Graphic novel it can be said that he is a young man since he has only being working for the company five years but he is in debt with them, and all his family depends on him, they also have a photograph of him about his military service on the wall. In the graphic novel it seems to be older now that he has been 15 years in the company and maybe he started after military service

Explanation:

It can also be inferred the absurdity of the universe in which it doesn’t matter how good you are, for instance Gregor is a good man how has a job he dislikes just to cover his family expenses, and to pay his sister’s studies. It suggest the universe is an ungoverned place without any order of justice or punishment.

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1 year ago
Read the passage from "Ode on a Grecian Urn."
galben [10]

Answer:

D. "Love."

Explanation:

John Keats's "Ode on a Grecian Urn" is a recollection of when the poet addresses an ancient Grecian Urn. The lines in the question are from the second stanza of the poem.

This ancient item has a picture of a young man and his lover, him playing a pipe and she lying under a tree. Keats  exclaims that the unheard melodies that he is playing are much sweeter than anything else as they are unaffected by time. The young man may not be able to kiss his love but he should not worry for they are already engraved in the picture which will forever stay. They are frozen in time, with their beauty intact and their love will last forever no matter how time goes.

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1 year ago
Can you say that human,whale,and bat might belong to a common ancestral group?
Molodets [167]
Humans, whales and bats have one thing in common: they're all mammals. This means that they have a common ancestor that is not shared by for example fish: in this way, they can be said to have a common ancestor, the first mammal.

However, in the end, all life on earth can be trade to a common ancestor- so to some degree this can also be said about all animals.
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2 years ago
Instructions:Drag each tile to the correct location. The poems “I, Too” by Langston Hughes and “From the Dark Tower” by Countee
Margarita [4]
A reference to Walt Whitman's "I Hear America Singing" => "I, Too". Langston Hughes' poem adds the African American identity to Whitman's list of ordinary people who constitute and contribute to American collective identity.

Paradox of social injustice => "I, Too". Hughes depicts the social inequality of black people, who are traditionally confined to servitude. He hopes, however, that this will change eventually.

Uses set meter and rhyme scheme => "From the Dark Tower". The poem's rhyme scheme is ABBA.

Symbol of wasted effort => "From the Dark Tower". Black people are the ones who plant, while white people reap.

Stone of anger and resentment => "From the Dark Tower". It depicts black people's anger at being constantly and systematically oppressed.

Uses free verse => "I, Too". Hughes' poem has a conversational tone. The free verse depicts the inner freedom that the speaker feels, and wants to transform into real freedom and equality.
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2 years ago
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Nesterboy [21]

Answer: They propel the plot of a story.

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2 years ago
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