In "Princess September," how has Maugham shown that jealousy can reach extreme heights leading to the suffering of others?

In the story "Princess September," jealousy can be found within the title character's sisters.  Because the princess of Siam, named Princess September, was the last daughter to be born, she was not subject to having her name changed again and again.  First, the king of Siam named the daughters (when he had only two) after day and night.  Next, the king renamed them after the seasons (when he had four).  Third, the king renamed them after the days of the week (when he had seven).  Finally, the king was in the middle of renaming all of them after the months of the year when Princess September was born.  The remaining children were boys; therefore, the king ceased the naming escapade.  All of these name changes caused the older princesses to be jealous of Princess September.  In fact, when Princess September receives a beautiful bird as a gift, the sisters convince her to lock the bird in a cage.  Before being caged, the bird gave Princess September much happiness.  The sisters wanted to take away that happiness due to their jealousy; therefore, they "suggested" caging the bird.  Of course, as soon as the bird was caged, it stopped singing and interacting with Princess September.  Princess September became so distressed that she set the bird free.  Thus, you can see how the sisters' jealousy led directly to Princess September's unhappiness.

In Incidents in the Life of a Slave Girl, why does Linda fear her master, Dr. Flint?

Quite simply, Linda fears Dr. Flint because he is her master. As such, Dr. Flint verbally abuses her and harasses her sexually. In regards to verbal abuse, here is a good example of his typical threats:

By heavens, girl, you forget yourself too far! Are you mad? If you are, I will soon bring you to your senses.

In regards to sexual harassment, the reader learns that Linda is given a "scanty wardrobe" as she grows. This is solely for the purpose of pleasuring Dr. Flint. When Linda figures out his purpose, Harriet Jacobs reveals it in this way:

[Linda] will become prematurely knowing in evil things. Soon she will learn to tremble when she hears her master's footfall. She will be compelled to realize that she is no longer a child. If God has bestowed beauty upon her, it will prove her greatest curse.

Note that this is the perfect quotation to prove the fear that you ask about in your question. Linda finally begins to "tremble" with fear "when she hears her master's footfall." Unfortunately, it is a typical situation in the life of a female slave that the author, Harriet A. Jacobs, helps the reader understand. What is interesting is that Linda considers this a normal part of slave life.

Linda continues dealing with this abuse until she escapes. The one thing that puts Linda over the edge in regards to escape is not concern for her own welfare but concern for the welfare of her children. Dr. Flint and his wife are finally moved into the new home on the plantation, and Linda finds out that "My children were to be brought to the plantation to be 'broke in.'" This is the last straw for Linda. She escapes first to her friend Betty's house. Finally, Linda switches to her grandmother's small attic space where she can safely observe the lives of her children (and others) while still maintaining her freedom.

What have scientists found to be the most efficient and effective way to insert new sequences into an individual's DNA?

The current state-of-the-art method for editing DNA is based on CRISPR, which stands for "Clustered regularly interspaced short palindromic repeats."

While scientists have had the ability to tinker with DNA for decades now, it wasn't until just a few years ago that CRISPR allowed them to modify DNA in specific individuals with great precision and speed—and very low cost.

It's actually based on a defense mechanism certain bacteria evolved against viruses; in the bacteria it targeted specific sequences of virus DNA to destroy them, but we now use it to target specific sequences of any DNA and modify them.

CRISPR allows us to modify multiple genes at once, and do it all in a single generation—indeed a single individual if we want. Where previously we tried to haphazardly introduce genes heterozygously into mouse embryos and then bred them until we got what we want, now we just fire up the CRISPR and modify that specific gene in that specific mouse.

It also works on just about any species—indeed, there's no reason to think it wouldn't work on humans. This raises all sorts of ethical questions, however: Now that we have this amazing technology, how should we use it? What risks does it pose? Who should have access to it?

How did the effects of World War I help Hitler come into power?

The Versailles Treaty ended World War I. This treaty was very harsh on Germany. Germany had to pay $33 billion in reparations to the Allies. Germany had to accept responsibility for World War I. Germany had to give up land and could only have a military capable of defending itself. Germany was very unhappy with the terms of the Versailles Treaty.

After World War I ended, Germany experienced difficult economic times. The economy went into a depression. Hitler suggested that if he was given political power, he would avenge the mistreatment from the Versailles Treaty. He said that the German people should not accept being treaty so poorly. He also promised to put the people of Germany back to work.

Since there were difficult economic times and since the German people were angry, they were willing to listen to Adolf Hitler and eventually support him as the leader of Germany.

When was Phillip's ship torpedoed?

The short answer is that the S.S. Hato was torpedoed on April 6th, 1942. But we can actually answer this question in a few different ways:

First, in terms of the plot of the novel, Phillip's ship being torpedoed happens in the beginning of the rising action. That is, after the exposition, in which we saw how Phillip and his family lived on Curacao during the war, the rising action begins as Phillip and his mother board the ship to try to escape to the safety of Virginia. That's when the ship gets torpedoed, leading to the rest of the action of the story.

Second, in terms of where in the book we'll find this event, Phillip's ship being torpedoed happens in the first paragraph of Chapter 3.

And lastly, just in relation to the natural timeline of history, although this story is fictional, Phillip's ship being torpedoed happens very early the morning of April 6th, 1942. You can find this information at the very beginning of Chapter 3.

Temperature and pressure are inversely related, so how, in the core of the Earth, are both temperature and pressure high?

Temperature and pressure are not inversely proportional. In fact, if the volume is held constant, temperature and pressure are directly proportional to each other. One way to think about it is to understand what happens when we increase the temperature of a substance. When the temperature increases, the molecules comprising the substance gain kinetic energy and start moving faster. When that happens, their collisions with each other and with the material they are held in (especially for fluids) increases and this causes an increase in temperature. The same is observed when we cook something in a pressure cooker or boil water for making tea or coffee.

Thus, it is entirely feasible for the temperature and pressure to increase simultaneously, provided the volume is held constant. In the earth's core, the temperature and pressure both are very high, and it is estimated that the core is divided into two parts. The external layer is liquid, while the inner core is solid (due to very high pressures, iron cannot melt, even at high enough temperatures).

Hope this helps. 

`x^2 + xarctany = y - 1 , (-pi/4, 1)` Use implicit differentiation to find an equation of the tangent line at the given point

Does the given point belongs to the given curve?

`x^2 + x arctany = pi^2/16 - pi/4*pi/4 = 0,`  and  `y - 1 = 0` also.

Then equation of the tangent line is `(y - 1) = (x + pi/4)*y'(-pi/4).` Perform implicit differentiation to find `y':`

`2x + arctany + x (y')/(1 + y^2) = y',`

solve this equation for `y':`

`y'(x) = (2x + arctany)/(1-x/(1+y^2)).`

At the given point it is equal to  `-(2pi)/(8+pi),` and the equation of the tangent line is

`y = 1 - (x + pi/4)*(2 pi)/(8+pi).`