What is the argument and logical content of the poem?

In the poem "Siren Song," Margaret Atwood uses the Greek myth of the siren, who lures men "to leap overboard in squadrons / though they see the beached skulls," to provide a vehicle for her core argument. In the poem, which is written in the voice of the Siren herself, Atwood argues that the "secret" of this siren song, which can induce men to leap into obvious danger where many have evidently suffered before them, is a "boring song, but it works every time." The core of the song is that the siren is saying

Help me!Only you, only you can,you are unique.

The argument of the poem, then, is that the desire to be considered unique—to be the only person who can help someone else—can induce us to throw ourselves into danger despite all available evidence that we will fail. This cry for help appeals to the sense of exceptionalism in us, which makes us feel that, although "beached skulls" lie before us, whatever has happened to others will not happen to us. In our desire to be "unique / at last," we will continually attempt to help people who cannot be helped and allow ourselves to be lured into situations from which nobody before us has ever been known to escape. For the sake of ego, we will leap into uncharted waters "every time."

What are the ways in which people are robbed of their humanity through alienation in Narrative of the Life of Frederick Douglass and “Life in the Iron Mills”?

There are many ways people are robbed of their humanity in The Narrative of the Life of Frederick Douglass. One way is, as you mentioned, through alienation. Slaves are alienated from the rest of humanity through the denial of their identity.
In Douglass's time, slaves could not properly ascertain their age. They were not allowed to have official records of their date of birth. Therefore, slaves could only guess at their age, a major source of unhappiness for Douglass throughout his life. For their part, slaves could not even ask their masters for information about any part of their background, as such inquiries were considered "improper and impertinent."
Douglass was also kept in the dark about his paternal heritage. Others mentioned that his father was white, but Douglass had no means of ascertaining this fact. Additionally, Douglass was also parted from his mother when he was still an infant. It was then the custom of slaveholders to keep female slaves estranged from their children. This is another way in which slaves were kept alienated: they were denied the opportunity to form strong familial bonds. Thus, they were robbed of their humanity. Douglass's mother died when he was seven years old. Tragically, he was never allowed to visit her during her illness, and he was even denied permission to attend her funeral.
Slaveholders also robbed their slaves of their humanity by denying them equal access to the justice system that whites depended on. Thus, slaves had no legal rights. In fact, killing a slave was not even considered a crime. Men killed slaves with impunity and boasted of doing so openly. Douglass relates how his wife's cousin was brutally murdered by the wife of Mr. Giles Hick. The young girl had been tasked to watch Mrs. Hick's baby. Due to her lack of sleep, however, she failed to hear the baby's cries one night. Finding that her slave was slow to move, Mrs. Hicks picked up an oak stick and broke the girl's nose and breastbone. The girl died not long after.
We find the same sort of inhumanity and alienation in "Life in the Iron Mills." In this story, the working poor are looked at with suspicion, distaste, and disapproval. They are treated as nothing more than disheveled specimens of humanity. Because many work in the steel mills, their bodies are often coated in grime. There is little opportunity or means of keeping clean. The workers are also paid poorly and must content themselves with living accordingly. Often, there is little to eat, and this causes malnutrition among the working immigrant population.
Since there is little opportunity for children in these communities to receive adequate schooling, many grow up with little hope of bettering their lives. Like their forefathers before them, they grow up to toil away in stifling hot steel mills. The workers are kept alienated from civilized society by their lack of education. Without education, social advancement is all but denied to them.

What gave Bigger's mother an insight to the kind of company Bigger keeps

The opening section of Native Son, titled "Fear," is as much focused on the conflicts within the Thomas family as on the poverty in which they live. Bigger's mother is aware of the "gang" he pals around with and blames them, partly, for Bigger's refusal to take jobs offered to him and for his disrespectful behavior to her and his sister, whom he taunts with the body of the rat he kills. Yet Bigger himself doesn't really like his friends Gus and G.H., and Mrs. Thomas is mistaken that they are the ones causing Bigger to behave irresponsibly and rebelliously. They're only a sideshow, a result of the overall problem and not the source.
Mrs. Thomas is correct that Bigger's "delinquency" is caused by influences outside his immediate home life, which is dire in itself but beyond her ability to change. It is understandable that she would attribute this to those with whom he associates outside the family. But Bigger's insight into his situation extends beyond what his family can imagine he is aware of. He perceives the injustice of the racist system of the time and the corruption of the white leaders, such as the State's Attorney candidate Buckley whose posters are plastered on the neighborhood walls. He articulates inwardly the reason for his anger, but says little to others beyond what is already obvious to them. Still, Bigger has no social mechanism available by which he can fight the system. The job with the Daltons would have made his mother happy, solved their money problems and freed him from the "gang" through which he would have landed in more trouble, yet Bigger finds his status as a servant intolerable, especially after Jan and Mary, through their ignorance, treat him with insensitivity and condescension. The murder of Mary, though partly accidental, represents an outpouring of Bigger's aggression which he had previously expressed in petty robberies with his friends. His mother, in having been mistaken that the friends had caused Bigger's problems, was thus also mistaken or in denial as to the root of Bigger'a anti-social behavior, and the severity of its consequences.

In "Self-Reliance," how did Emerson view the prayers of the people?

In "Self-Reliance," Emerson regards the prayers of most people, which are prayers of petition for worldly goods or favors, to be "vicious." These prayers are wrong-headed, in his opinion, because they rest on the assumption of a dualism between God and humans. In this thinking, God is a benefactor, up in heaven, separate from us. As Emerson puts it:

But prayer as a means to effect a private end is meanness and theft. It supposes dualism and not unity in nature and consciousness.

Actually, Emerson says, God is within us. We are united with God. Therefore, our prayers should be expressed through our actions, not our words. When a farmer, for instance, kneels in a garden bed to weed it, he is kneeling in prayer. When a rower kneels in his boat to pull the oars, this is prayer. When we show our oneness with God and our awareness of seeing life and the universe through the eyes of the highest good, this is prayer.
This connects with Emerson's idea that our life work should spring not from tradition, convention, or what our parents tell us to do, but from the divine source within us; then our lives become a form of prayer.

Emerson complains that mainstream prayer practices are petty and self-serving. He also complains that they presuppose a patron-client relationship with God. People often use prayer as an opportunity to act or beg God for a favor. Emerson sees prayer as a letter asking an external benefactor for outside help:

Prayer looks abroad and asks for some foreign addition to come through some foreign virtue.

This sharply contrasts with Emerson's ideas of what true prayer should be:

Prayer is the contemplation of the facts of life from the highest point of view. It is the soliloquy of a beholding and jubilant soul. It is the spirit of God pronouncing his works good.

If we unpack Emerson's words, we find several points. First, true prayer isn't supposed to be about registering personal dissatisfaction and asking for a remedy. It's supposed to be about contemplating the big picture and rising above one's immediate circumstances to appreciate the excellence of God's works in general. It's supposed to be an expression of joyful approval, not a letter of complaint or plea for help.
Second, the whole notion of God as a separate entity is wrong. When we pray, we should be turning inward to the part of ourselves that is part of God. We share God's spirit, see things from God's point of view, and rejoice in creation.
The common approach to prayer is entirely off the mark. It separates human beings from the spirit of God, and turns prayer into a petition for a bail-out.

The following sentence is ambiguous. Provide two explanations which illustrate the different meaning of the sentence: Visiting relatives can be problematic.

The sentence is unclear because one is unsure if the speaker is talking about the act of visiting relatives being problematic or if relatives who are visiting can be problematic. Let's break each possibility down grammatically.
The first possibility focuses on the act of visiting relatives. "Visiting" in this case is a gerund referring to an action -- the thing that is being done. "Relatives" are the direct object here, or the group being visited. The modal phrase "can be" is epistemic -- that is, it will lead us to the adjective that will tell us more about what it is like to visit relatives. In this case, the adjective is "problematic."
The only thing that is consistent between the two possibilities is the negative connotation of "problematic." Now, let's consider the second grammatical possibility. The phrase "visiting relatives" could be a subject clause. "Visiting," in this case, acts as a present participle adjective, modifying "relatives." The modal phrase "can be" now takes the form of a linking verb. Linking verbs connect the subject to parts of speech, such as adjectives, that will tell us something more about the subject. In this case, "problematic" is used to describe "visiting relatives."
This sentence could be clarified by beginning instead with an infinitive clause, though that can be awkward in modern speech: "To visit relatives can be problematic." One could also begin with a more specific gerund: "Going to visit relatives can be problematic." Finally, if one wants to focus on the relatives themselves one could write, "Relatives who are visiting can be problematic." The relative clause "who are visiting" describes the relatives to whom we are referring.

List and explain the features of Communism.

Communism, as an ideology, is an extremely broad moniker that is applied to a number of (sometimes contradictory) positions. However, all forms of communist ideology are rooted in the writings of Karl Marx (1818 - 1883) and Friedrich Engels (1820 - 1895) and share a number of common features. As a short answer, the chief features of communism are
The belief in a classless, stateless, propertyless society (communism);
The belief in a violent revolution to bring about communism; and
Opposition to capitalism.
While many implementations of communism in the 20th century attempted to bring about a communist society through an authoritarian regime, this isn't a universal feature of communism and is mostly associated with the writings of Vladimir Lenin (1870 - 1924). Anarcho-communists, informed by the writings of Peter Kropotkin (1842 - 1921), don't advocate for a state at all, and instead want to abolish it along with capitalism.
As a (very) long answer:
A central facet of Marx's theories has to do with the means of production. A means of production is essentially anything that can be used to produce commodities -- things that can be bought, sold, and consumed. An example of a means of production is a factory. Under capitalism, what Marx considered to be the predominant economic system of the day, the means of production are privately owned. For example, imagine someone who owns a textile factory, and hires workers to work in the factory. Marx would refer to those who own the means of production as the bourgeoisie (upper class) and the workers as the proletariat (working class.) Under socialism, the economic system Marx believed would follow capitalism, the proletariat would control the means of production by themselves. The proletariat would "seize the means" after a violent revolution.
This, in a nutshell, is the main theory behind communism. However, this is where Marxists begin to disagree with each other. Marxists primarily tend to argue about whether or not a state is absolutely needed to bring about communism. Marx himself believed this -- he called it the dictatorship of the proletariat, where the workers would form a government that represented their interests, which would eventually wither away, leaving true communism. Some communists, such as the previously mentioned Peter Kropotkin, disagree, however, and see the state as equally dangerous as capitalism.
Marxists also tend to disagree on the revolutionary subject -- that is, who is responsible for producing the revolution that will eventually lead to communism. While most communists agree the working class in industrial capitalism is the revolutionary subject, some, like Mao Zedong (1893 - 1976) believe that the rural, third world peasant will lead revolution. This is referred to as Third Worldism and is popular in Asia.
Communism is an extremely broad ideology, but all communists are united in their opposition to capitalism and support of revolution.

The basic tenets of Communism are based upon Karl Marx's founding text, the Communist Manifesto, which he wrote in 1848. Marx believed that the ideal society would be classless and that in order for this to be achieved, the "means of production" would have to be nationalized; the government would then be able to control all the country's wealth and distribute it equally.
In a Communist society, then, there is a strong central government which controls education, labor, transportation, agriculture, and the distribution of money. Communist societies, according to Marx, should also completely abolish the private ownership of property and confiscate the private property anyone owned before the revolution. This formed the first phase of his stipulated plan for establishing such societies. Supreme government authority would also mean that everyone's income would be heavily taxed in order to be redistributed equally, meaning that, theoretically, nobody should languish in poverty and a welfare state would provide care for all.
In actuality, Marx's theory—which he never put to the test—proved more difficult to implement than he had hoped, as it relies upon governments to be honest; a corrupt government can easily assert too much control, leading to the deaths of many citizens and the concentration of power and money among those who will abuse it.
https://www.marxists.org/archive/marx/works/download/pdf/Manifesto.pdf

Would it be correct to say that Jude the Obscure is the last of the Victorian novels and first of the modern ones?

No, it would not be correct to say that Jude the Obscure by Thomas Hardy "is the last of the Victorian novels and the first of the modern ones." First, this assumes that there is a clear demarcation between Victorian and Modernist fiction and that they can be distinguished as easily as one might distinguish dogs from parrots. That is simply not the case; as Wayne Booth points out, many of the features that some claim to be distinctively modern, such as intrusive narrators, actually are present throughout the entire history of the novel.
Jude the Obscure was serialized beginning in 1894 and first appeared in book form in 1895. As Queen Victoria reigned from 1876 through 1901, this publication date is toward the end of her reign, but it is far from the last novel published in the Victorian era.
In terms of theme, Jude the Obscure addresses the problem of a sensitive young man who is intelligent and self-educated but born into poverty, who fits neither in the class of his origin nor in the educated upper classes. This is a theme one finds in many late Victorian novels, and it addresses the issue of how increasing social mobility ran up against the glass ceiling of entrenched class structures. The treatment of women in this novel is also fairly typical of how late Victorian literature engaged issues of the "new woman" and changing gender roles and expectations. The unrelenting despair and sense of the ultimate fruitlessness of Jude's struggles is something found in other Victorian novels, such as Gissing's New Grub Street.
Technically, the novel is quite typically Victorian, as it is designed for serial publication and written in the third person, with the narrator having full access to Jude's thoughts and some of the thoughts of other characters. The narrator is reliable, time is handled sequentially, and events described realistically.