I have to write an essay about how the Camelot in Arthurian texts is similar to the presidency of John F. Kennedy. The only problem is I'm not sure...

It sounds as though you are struggling on this assignment but have made a good start in understanding why you are having issues with it. 

The first issue seems to be understanding Le Morte d'Arthur. This text was first published by Caxton in 1485 after the death of its author Thomas Malory. It is written in Early Modern English which is comprehensible by speakers of modern English but requires some concentration. There are two ways you can help yourself understand the book. The first might be reading a modernized version such as that by Peter Ackroyd or the  before returning to tackle the original so that you have a sense of the overall plot. Next, you should set yourself a goal of reading one chapter at a time with no distractions (phone off, music off, TV off) and taking notes and highlighting as you read. You might also make index cards for each major character, and as you read, whenever something important happens to a major character such as Merlin or Arthur or Mordred, adding a note to the card for that character.

The association of Kennedy's presidency with Camelot had its origin in a interview between Mrs. Jacqueline Kennedy and a journalist for Life magazine shortly after Kennedy's assassination, in which she applied a quotation from the popular Broadway musical Camelot to her husband's presidency saying:

Don’t ever let it be forgot, that once there was a spot,

for one brief shining moment that was Camelot.

In your essay, you should outline points of comparison between Kennedy's presidency and Arthur's kingship. The first parallel is that Kennedy was both a charismatic and highly polarizing figure who won the popular vote by less than one percent, just as Arthur was also not universally accepted. Also, Kennedy was youthful and assassinated in the prime of his life, like Arthur.

Next, the Round Table was intended as a gathering of the greatest knights in the world. Kennedy famously gathered around him many distinguished thinkers and intellectuals, the "best and the brightest" of his generation; you could draw parallels between the Kennedy Cabinet and the Round Table.

You might also want to introduce another parallel between Kennedy and Arthur, namely that both were rather notorious philanderers, with Arthur's downfall being caused by his illegitimate son and Kennedy's staff struggling to keep his many affairs away from the press. 

What is the conflict of the story The Odyssey?

The Odysseyby Homer is an epic poem that tells the story of Odysseus' journey home. While there are many, many conflicts that happen throughout the story that covers 20 years, which is how long it took for Odysseus to get home after the Trojan War, the main conflict is Odysseus trying to get home. He is met with many obstacles and challenges that he must face and overcome, and there are conflicts within all...

The Odyssey by Homer is an epic poem that tells the story of Odysseus' journey home. While there are many, many conflicts that happen throughout the story that covers 20 years, which is how long it took for Odysseus to get home after the Trojan War, the main conflict is Odysseus trying to get home. He is met with many obstacles and challenges that he must face and overcome, and there are conflicts within all of these, but the largest conflict is him trying to go home.

Some of the smaller conflicts or challenges that Odysseus faces throughout his journey are the monsters Scylla and Charybdis, the cyclops Polyphemus, and getting stuck on an island, as well as the wrath from multiple gods like Poseidon and Helios. When he does finally arrive home, he faces the large conflict of the suitors, who have taken over his house in his absence and have been trying to take his wife as well. Odysseus kills them all.

In spite of all the conflicts that Odysseus faces, he succeeds in arriving home to his wife and son after being gone for 20 years. He completes his odyssey. 

In the play "Death of a Salesman" how are Biff and Willy idealists?

Biff and Willy both look to each other for inspiration. This, I believe, remains true for Biff even after he becomes disillusioned with his father after discovering Willy's infidelity in Boston. Later in his life, he still works to fulfill his father's grand expectations for him, such as talking about going into a sporting goods business with his brother, Happy. However, by the end of Act Two (which is when Willy dies), he gives up...

Biff and Willy both look to each other for inspiration. This, I believe, remains true for Biff even after he becomes disillusioned with his father after discovering Willy's infidelity in Boston. Later in his life, he still works to fulfill his father's grand expectations for him, such as talking about going into a sporting goods business with his brother, Happy. However, by the end of Act Two (which is when Willy dies), he gives up -- accepting that the reality of who he is and his father's hopes for him are irreconcilable. 

Because we learn about Biff as a young man through his father's recollections, which are unreliable, we cannot be completely sure about who Biff really was in his high school years. We do not know if he was truly as beloved as Willy remembers, or even if he idolized his father to the extent to which Willy remembers. If we are to believe Willy's recollections, however, it seems that, for Biff, Willy was a masculine ideal: a capable businessman, a great talker, and a well-liked man.

After he discovers his father's infidelity, this ideal dissolves. Biff's response to this disappointment is to leave New York and to go out West to start a farm. In this play, Miller uses applies to the West all of the tropes and associations that the region bears in popular culture: it is the place where people go to start over, the place where men go to create their own fortunes. Biff fails, though, even in this idealized space. 

On the surface, Biff's ideal for success is really influenced by his father's expectations. After Willy's death, he is free to abandon the ideal. He knows that he will never run a sporting goods business, or be a "number-one man." Willy's ideal is for his son to be the success that he never was. 

On a deeper level, one can say that Willy and Biff are examples of how the American Dream is unrealistic. The dream is that every man (and, in the context of this play, particularly, the fantasy is very masculine) can succeed using his individual talents; and that every man has the potential to create his own fortune. This does not turn out to be true for either Willy or Biff. Neither is particularly talented, and both make bad choices. 

Why is Jerry no longer interested in the French boys at the end of the story?

At the beginning of the story, Jerry strongly desires the acceptance of these boys. The narrator tells us

They were of that coast, all of them burned smooth dark brown, and speaking a language he did not understand.  To be with them, of them, was a craving that filled his whole body [....;] as he preserved his nervous, uncomprehending smile, they understood that he was a foreigner strayed from his own beach, and they proceeded to forget him. But he was happy. He was with them.

These boys are older than Jerry, and he very much wants to be on their level. Their cool turn-taking and nonchalance about swimming underwater through the rock frightens Jerry and makes him feel different from, lesser than, them. The tunnel through the rock can be read as a symbol of the passage to adulthood, and these "big boys -- men to Jerry" pass through it with ease, whereas Jerry knows there is no way he could even attempt such a feat now. He understands, after his fruitless attempts to draw their attention back to him, that 

They were leaving to get away from him.  He cried openly, fists in his eyes. There was no one to see him, and he cried himself out.

Like a child, he cries when he sees that he is not equal to them, not accepted by them as a peer.  

By the end of the story, however, Jerry has made a plan in order to be able to swim through the rock as the "big boys" have done. He has practiced and worked hard, and still he holds off attempting the feat because he wants to be sure he is really prepared. The narrator says, "A curious, most unchildlike persistence, a controlled impatience, made him wait." Jerry is beginning to develop from a child into an adult. He now looks back on the beach he used to play on with his mother as "a place for small children [...]. It was not his beach."

In the end, after he has literally bled and nearly died to achieve what the older boys accomplished so easily, "He did not want them." Jerry has realized that he's not quite ready to be one of the big boys yet; he's not ready to be an adult (though he has begun the process of developing into one).  This realization is further supported by Jerry's childish behavior with his mother in the final lines. Calling her "Mummy" (as a child would), and clearly hoping for her praise, he blurts out that he can now hold his breath for almost three minutes. He no longer seeks the approbation of the older boys; he is content with his mother's praise, as a child would likely be, because he recognizes that he just isn't ready to be "a man" yet.

How do I consider Hamlet and identify the ways in which Shakespeare's dramaturgy shifts from the form of Aristotelian tragedy?

Shakespeare departed from the Aristotelian model in many ways, although it’s not clear that he did so consciously. We don’t know for certain that Shakespeare ever read Aristotle's “Poetics” or was aware of its principles. His ideas about tragedy may have come more from watching his contemporaries’ plays and the mystery plays and other sorts of drama that were popular at the time, which were themselves in part indebted to Aristotle. It's entirely possible that...

Shakespeare departed from the Aristotelian model in many ways, although it’s not clear that he did so consciously. We don’t know for certain that Shakespeare ever read Aristotle's “Poetics” or was aware of its principles. His ideas about tragedy may have come more from watching his contemporaries’ plays and the mystery plays and other sorts of drama that were popular at the time, which were themselves in part indebted to Aristotle. It's entirely possible that Shakespeare just wanted to write an interesting play and was not thinking about Aristotle at all.

That said, “Hamlet” does have both elements that follow Aristotle’s principles and elements that would have set Aristotle’s teeth on edge. Aristotle believed that a tragedy should be rooted in the experience of a single protagonist (which “Hamlet” is), and that the protagonist needs to have some amount of stature, often royalty, so that when they fall over the course of the play they have a long way to fall (check). He also believed that the main character should be brought low by some tragic flaw within himself, and here “Hamlet” begins to waver from Aristotle: although Hamlet is a deeply flawed character, his tragic fate doesn’t entirely hinge on some fault within him that can be easily identified. Aristotle also believed that the tragedy should take place entirely in one location (nope) and that the action of the play should contain no jumps in time: the length of the performance is exactly the amount of time that the characters experience (“Hamlet” doesn’t do this at all, though “The Comedy of Errors” and “The Tempest” both do). In a strictly Aristotelian tragedy, there is also no room for comedy; he believed that tragedies should focus on the tragic and noble characters and that laughs and lower-class characters should be confined to comedy. Shakespeare had absolutely no interest in separating tragedy and comedy: his tragedies are full of humor; his comedies are often full of very disturbing things. The gravedigger scene in “Hamlet” is completely at odds with what Aristotle thought a tragedy should be, for instance, so while Shakespeare borrows some of Aristotle's ideas it is very clear that he was not interested in all of them and in fact the ones that he followed he may have followed purely by coincidence and not out of a conscious sense of obligation to Aristotelian ideas.

How does Birnam Wood arrive at Dunsinane?

This, of course refers to the prophecy by the third apparition summoned by the witches that Macbeth can never be "vanquish'd" until "Great Birnam wood to high Dunsinane hill/Shall come against him." Macbeth takes the prophecy literally, and since it seems very unlikely that Birnam Wood, a forest, will physically march up a hill against Dunsinane (his palace) he interprets the prophecy to mean he can never be destroyed. He is shocked, then, in Act...

This, of course refers to the prophecy by the third apparition summoned by the witches that Macbeth can never be "vanquish'd" until "Great Birnam wood to high Dunsinane hill/Shall come against him." Macbeth takes the prophecy literally, and since it seems very unlikely that Birnam Wood, a forest, will physically march up a hill against Dunsinane (his palace) he interprets the prophecy to mean he can never be destroyed. He is shocked, then, in Act V Scene 5, when one of his messengers comes with the news that the forest is moving up the hill against him. We learned in the previous scene that Malcolm ordered his men to hew off boughs of wood to use as cover as they advanced. The marching soldiers, each carrying tree branches, look like a forest. So it turns out that the prophecy was somewhat misleading, as was the prophecy that no man "of woman born" could destroy him. Macduff, it turns out, was born by Caesarian section. So the witches' prophecies have filled Macbeth with misplaced confidence that he can carry out his schemes with impunity.  

Describe the reaction mechanism of a SN 2 - reaction for example the reaction of a hydroxide ion (OH -) (nucleophilic) reacts with a molecule of...

An SN2 reaction is a common reaction in organic chemistry, which is chemistry involving compounds formed with the element carbon.  In this reaction, two reacting species are involved, so the term SN2 is used, meaning "substitution nucleophilic 2". 

This reaction involves the bromide ion (Br-) being replaced by the electronegative hydroxide ion (OH-).  The attack usually occurs at an unhindered carbon atom on the methyl group.  The old bond between the carbon and the bromine...

An SN2 reaction is a common reaction in organic chemistry, which is chemistry involving compounds formed with the element carbon.  In this reaction, two reacting species are involved, so the term SN2 is used, meaning "substitution nucleophilic 2". 

This reaction involves the bromide ion (Br-) being replaced by the electronegative hydroxide ion (OH-).  The attack usually occurs at an unhindered carbon atom on the methyl group.  The old bond between the carbon and the bromine is broken, while the new bond between the carbon and the hydroxide group is established.  Both these bonds are covalent in nature, meaning the electron is shared between the two groups.

In this reaction, the methyl group (CH3+) is the electrophilic part of the equation, as it needs an electron to complete the balance between the charges.  The hydroxide group (OH-) is the nucleophilic part of the equation, as it has a need to balance the negative charge on it.  The hydroxide group serves as the attacker, substituting for the bromide (Br-).  The product would be methanol (CH3OH) and bromide (Br-) in aqueous solution.

The reaction would look like this:

H3CBr  +  -OH  ----->  H3C+  (-Br)  +  -OH

H3COH  +  -Br (aqueous)