In Macbeth, in what situations besides the murder of Duncan does Macbeth show lust for power?

Apart from his own ambition and desire to become King, Macbeth is greatly influenced by Lady Macbeth. He is proud of his physical courage, and is therefore more vulnerable, for instance, to her suggestion in Act 1, sc 7, that he is not a real man if he does not act decisively in relation to Duncan.

  ...Art thou afear'd

To be the same in thine own act and valour

As thou art in desire? " 

She asks whether  he would rather give up his hopes of becoming king 

"And live a coward in thine own esteem...."

Macbeth replies to her critisim with the strong retort "I dare do all that may become a man" but is still influenced by her comeback "When you durst do it, then you were a man". In this scene, the audience sees Macbeth's resolve developing. At the start of the scene he is still unconvinced, and wrestles with the immorality of killing the king. By the end of the scene, however, his wife has convinced him. 

"I am settled, and bend up

Each corporal agent to this terrible feat".

Later in the play, Macbeth's lust for power has grown to such an extent that he cannot even bear to think of Macduff having snubbed him by refusing to attend the banquet. He sees this as a threat to his complete power and control over the thanes, and that is one of the reasons that he visits the witches a second time.

Finally, Macbeth craves the power of self determination. When he knows that he is beaten, he makes a conscious decision to fight to the death , rather than  be taken alive, where he might have to "kiss the ground before young Malcolm's feet" ( Act 5, sc 8).

How do mitochondrion and all other organelles assist eachother by working together?

Mitochondria are the powerhouses of the cell. They supply nearly all the required biological energy. Only the mitochondria are fully capable of converting pyruvic acid to carbon dioxide and water. Mitochondria are the respiratory centres of the cell. Cell respiration can be divided into four phases: 1) glycolysis, 2) oxidation of pyruvic acid, 3) krebs citric acid cycle and 4) oxidative phosphorylation through the hydrogen/ electron transport system. Glycolysis involves the breakdown of glucose to pyruvic acid. The enzymes for glycolysis are found in the cytosol, outside the mitochondrion. During oxidation of pyruvic acid, Pyruvic acid is degraded to acetyl-CoA, with the liberation of a pair to hydrogen.

Why does the chorus tell the whole story? Did he ruin the story for us? Why does he tell us that the play will only last two hours?

It is important to keep several points in mind when considering the purpose of the Chorus. The Chorus speaks twice in the play, before the beginning of Act I and before Act II. It functions as a commentator on the action and basic meaning of the play. It sets the scene in Verona, Italy, and summarizes the action. Traditionally, choruses served as the voice of public opinion in Greek tragedies, often reviewing the plot and offering moral judgments on the participants. Here, the Chorus seems to reserve the judgment, while still explaining the plot for the audience.

It is significant that the plot of Romeo and Juliet was taken from an earlier version of the story. The theme appeared in the fourth century in a Greek tale and later in the sixteenth century. In the later version, the city is Verona, and it was the first to call the hero and heroine Romeo and Giulietta. Probably Shakespeare’s most direct source was a long English narrative poem written in 1562 by Arthur Brooke, called The Tragicall Historye of Romeus and Juliet. Shakespeare used the characters in Brooke’s poem but developed them in much greater depth and detail, thus transforming the story of star-crossed lovers into the most famous love story ever known.

So Shakespeare didn't invent this story. His contemporaries knew the basic story, and some may have read the longer poem. Thus, the Chorus wouldn't be reealing anything they didn't already know. Indeed, as his play-goers were coming to see a tragedy, they would pretty much know how it was going to end. The only new bit of detail would be the length (hence the "two hours traffic of our stage") and perhaps the setting. Also, since the orginal basis was a Greek tale, he may have been attempting to conserve the traditional format.

Finally, I don't think the Chorus ruins the story at all. By now, practically everyone who's familiar with popular American or British culture knows the story of Romeo & Juliet by the time they're 10, and thus the deaths come as no surprises. Even modern audiences have an idea that a tragedy will end in death for many characters. The beauty of this play lies not in knowing how it ends, but in following the journey of the lovers through their brief but passionate affair. The Chorus does not tell us of the fights, the tears, the vows of love that come along the way-and that is where the true meaning of the play is found.

In act 4 how would you summarize the way circumstances have worked so far for Juliet?

Tragically conflicted.  With Juliet already married to Romeo Scene I of Act IV finds Paris pressuring Friar Lawrence to set a date for Juliet and himself to be married.  Of course, Friar Lawrence is in a quandary since he knows Juliet is already married, but he cannot inform Paris of this.  More conflict of intentions occurs in Scene II as Lord Capulet insists that Juliet marry Paris, but she acts compliant:  "Henceforward I am ever ruled by you."  Then, she plays the middle ground of ambiguity,

I met the youthful lord at Laurence's cell;/And gave him what becomed love I might,/Not stepping o'er the bounds of modesty [I did not say I love him, but I did not say that I did not, either] (IV,ii,23-25)

In Scene III, Juliet drinks the potion, which, of course, causes a grave problem when the Capulets discover her and in Scene V, wedding plans conflict with funeral plans.  Juliet goes to church, not to be married, but to be buried.  Lord Capulet speaks in contrasts:

All things that we ordained festival/Turn from their office to black funeral;/Our instruments to melancholy bells,/Our wedding cheer to a sad burieal feast,/Our solemn hymns to sullen dirges change,/Our bridal flowers serve for a buried corse,/And all things change them to the contrary (IV,v,74)

How does Edgar Allan Poe create the mood of melancholy in this excerpt of his poem, "The Raven"? "Deep into the darkness peering, long I stood...

There are many devices which make this excerpt "melancholy," but I will focus on two: imagery and sound.

First, the imagery presented draws a dark and mournful picture in the reader's mind's eye. Words like darkness give the impression of grief and loss, and this diction combines with our second factor, sound, to give the reader the general indication of sadness.

Sound, as used by Poe in this excerpt, is intentionally meant to sound like a funeral dirge. Think of words like "Lenore, before, and more." All three have the drawn out sound of the short "O" combined with a hard "R."  This is done intentionally, as Poe was using the sound of language to connote grief, much like a sad piece played on a pipe organ. Had he used words like "bright, flight, sight, and might," those words would have carried a cleaner and altogether happier sound. As it is, however, Poe uses the above tools, imagery and sound, to let his readers know of his intimate sadness. 

What does Olivia reveal about herself through her words and actions in Act 4?

In Act IV Scenes 1 and 3, Olivia mistakes Sebastian the twin brother of Viola to be Cesario with whom she has fallen in love with. In Sc.1 she authoritatively breaks up the quarrel between Sebastian and Andrew Aguecheek and Sir Toby Belch and scolds Sir Toby in the following words:

Will it be ever thus? Ungracious wretch,
Fit for the mountains and the barbarous caves,
Where manners ne'er were preach'd! out of my sight!
Be not offended, dear Cesario.
Rudesby, be gone!

However, she draws Sebastian aside and affectionately controls him saying, "nay, come, I prithee; would thou'ldst be ruled by me!" Naturally, Sebastian is pleasantly surprised but willingly surrenders himself to be ruled over by her.

In Act IV Sc.3, Sebastian in his soliloquy reveals that he is too amazed at her strange conduct and wonders whether all what is taking place to him is real and finds it difficult to believe his eyes and is convinced that either he or Olivia is mad,

"that I am mad
Or else the lady's mad."

but he reasons that she can't be mad because,

"if 'twere so,
She could not sway her house, command her followers,
Take and give back affairs and their dispatch
With such a smooth, discreet and stable bearing
As I perceive she does."

From Olivia's words and actions we learn just as Sebastian does that Olivia is the mistress of her household and is an authoritative person who is accustomed to giving orders and having those orders obeyed. For she soon enters the scene with a priest and leads Sebastian to her chapel to get married to him :

"Blame not this haste of mine. If you mean well,
Now go with me and with this holy man
Into the chantry by: there, before him,
And underneath that consecrated roof,
Plight me the full assurance of your faith;
That my most jealous and too doubtful soul
May live at peace."

The last two lines reveal that Olivia is jealous and possesive just like any other normal young woman who is in love.

How do I solve for x, when 5x+3=-12

In an equation, both sides of the equal sign represent the same number, once all the math is done. An equals sign is like a see-saw: if an extra person gets on one side, then someone who weighs the same has to jump on the other side to keep the see-saw level. So you can add, subtract, multiply, or divide any number to one side of the equation as long as you do the exact same thing to the other side.

So, to solve for x in 5x + 3 = -12, we want to get x all alone on one side.

5x + 3 = -12

5x + 3 - 3 = -12 - 3           Subtract 3 from both sides

5x = -15                           Simplify

5x/5 = -15/5                     Divide both sides by 5

x = -3

Check the math:

5*(-3) + 3 =? -12

-15 + 3 =? -12

-12 = -12                      check.