Why can’t the men see the island from the yacht?

At the beginning of the short story, Whitney tells Rainsford that nearby is an ominous place referred to as Ship-Trap island. Unfortunately, Rainsford cannot see the island from the yacht because of the darkness that engulfs the ship. Rainsford mentions the night is like "moist black velvet" and tells Whitney he cannot see four yards in front of him. The moonless Caribbean night and the extremely dark atmosphere establishes the ominous, threatening mood of the story. Whitney proceeds to tell Rainsford that the island nearby has a bad reputation and says the sailors have been jumpy all day. Whitney describes the island as a "God-forsaken place" and tells Rainsford that he believes that evil is a tangible thing that he can feel. After Whitney goes below deck, Rainsford ends up hearing the sound of a gunshot coming from the island and accidentally falls overboard. Rainsford then swims to the island, where he is introduced to the maniacal General Zaroff.

Discuss one sample test of hypothesis, when "student t distribution" is used rather than the "normal z distribution" in hypothesis testing of the mean.

The short answer is that you use the student t-test when you do not know the population standard deviation.
When performing a hypothesis test for the mean, the null hypothesis is that the given population mean mu is correct and the alternative hypothesis is that the given population mean is incorrect. (The alternative hypothesis can be either one- or two-tailed; that is, we can assume the population mean is actually greater than, less than, or just different from the given mu.)
We test the null hypothesis by computing the critical value(s) and the test value. The critical value demarcates critical region(s). If the test value falls in a critical region, we reject the null hypothesis, otherwise we do not reject the null hypothesis. In order to compute the test value and the critical value(s), we must determine the type of test to run. If we know the population standard deviation, we can use the standard normal z-distribution. If, however, we do not know the population standard deviation we must use the student's t-distribution.
Without the population standard deviation we must use some approximation—usually the standard deviation of the sample. But we know that the sample standard deviation is too small, so we introduce a correction factor. The t-distribution takes into account the changing correction factor (determined by the sample size). For large samples, the t-distribution approaches the standard distribution.
Example: Suppose we are told that the average strawberry has 200 seeds. A random sample of 10 strawberries has a mean of 185.2 seeds with a standard deviation of 10. We want to test if the average number of seeds is actually less than 200.
1. The null hypothesis H0 is mu=200, while the alternative hypothesis H1 is mu<200
2. We use the t-distribution to compute the critical value as we do not know the pop. std. dev. From the t-table with d.f.=9 we get c.v.=-2.262
3. The test value is t=-4.585
4. Since the test value is in the critical region (p=.00065. We conclude that there is sufficient evidence to conclude that the population mean is less than 200.

What does the title of this chapter “Andy’s Final Phone Calls” seem to foreshadow in Tears of a Tiger?

The title of this chapter foreshadows Andy's tragic suicide. Andy has been finding it increasingly hard to live with the emotional pain caused by the fatal auto accident that claimed his friend Robbie's life. Ever since that terrible day, Andy's been suffering from severe depression, and on numerous occasions, he has seriously entertained thoughts of taking his own life.
The final phone call to which the chapter title refers was his last desperate attempt to get help. Consumed by suicidal despair, Andy calls Dr. Carrothers, a psychologist he's been seeing recently. Unfortunately, Andy's unable to get through, as Dr. Carrothers' mother has suffered a heart attack and so he's unavailable. Without anyone else to turn to, Andy tragically takes his own life, finally bringing his emotional pain and suffering to an end.

How does Aunt Polly's behavior poke fun at some of the medical practices of her time?

Aunt Polly’s remedies are not easy to swallow, as Tom learns the hard way (chapter 12). Tom makes the mistake of mooning around and thinking about the girl he likes, Becky. Aunt Polly notices his unusual behavior and decides he is sick. The crowning blow is a patent medicine called Pain-killer, which tastes so awful that Tom cannot bear to drink it. He feeds it to the cat, whose horrible reaction makes Polly realize that she has been overdoing it and finally desist.
The nineteenth century was the era of “patent medicines,” as people did not yet rely on doctors for everyday minor problems, but many were buying strange concoctions rather than making their own homemade tonics. The manufactured medicines were often largely alcohol but sometimes even contained cocaine or opiates. Aunt Polly had a gullible nature but also was genuinely interested in helping people. Her curiosity and hunger for novelty led her to buying and experimenting with what Twain calls, “all new–fangled methods of producing health or mending it.”
She subscribed to "Health" magazines (which were expensive in those days) and even believed in phrenology, a pseudo-science that diagnosed people by feeling the bumps on their heads. Twain lumps together her “quack periodicals and her quack medicines,” noting they were as likely to kill as to cure.

Why did Chester Arthur not have a vice president?

Chester Arthur ran with James Garfield as his running mate on the Republican ticket for president in 1880. When Garfield won, Arthur became the vice-president of the United States. Not long after Garfield took office in 1881, he was assassinated, and Arthur became president.
At this time, there was no established mechanism for appointing a vice president if a president died in office, so the vice-presidential position was never filled. It was not until the assassination of President John F. Kennedy in 1963 that the US Constitution was amended to correct this oversight. In 1967, the Twenty-fifth Amendment was enacted, outlining a clear path for the government to fill the vice presidential position should a president die in office or become incapacitated in some way.

Can we consider Sir Orfeo as a hero?

Yes, in many ways Sir Orfeo seems to mirror the elements of heroes of yore. He follows the typical mold for a traditional hero. Let’s analyze his heroism qualities and journey.
Orfeo is the King, and immediately, he has a pressing mission. The hero’s journey is a quintessential part of being a hero. He must travel to the Otherworld and save his wife. In this way, there is a romantic bent to his mission, showing his chivalry and care for his wife, which endear him more to the reader—another quality of being a hero.
When he reaches the Otherworld, he forges a contract with its king which allows him to get his wife and escape with her, showing his cunning and intellect, like Odysseus and other legendary heroes. Finally, upon returning home from his journey, he displays his might and reclaims his rightful place on the throne—an archetypal action in many hero stories. His last act in the story is to show favor to his assistant and make him their heir, showing his kindness and loyalty.
All of these traits exemplify his heroic nature. That, along with the standard hero’s journey, make him clearly a hero.

You have been hired as a consultant for an airline, Yorkville Airlines, headquartered in New Brunswick, Canada, which believes there is potential for outsourcing aircraft maintenance to the United States. Because of your knowledge of the United States, you have been asked to provide a report on the American business environment that would include overviews of the United State’s economic system and the role of government in conducting business in the United States. In addition to the overview, it should specifically outline how these compare to Canada.

The American business environment, meaning the sets of relevant circumstances under which American companies do business, is robust, advanced, and fertile for wide-ranging innovations. Relevant to the aeronautics industry, the United States is a known leader in manufacturing and technology needed in aircraft construction and maintenance.
The role of government in America's mixed economic system is a regulatory one, although private enterprise is emphasized. A mixed economy functions with both private enterprise and government regulatory policy playing a role in directing the economy. Government sets policies and regulates such areas as corporations, environmental impact, and labor rights. The power of private enterprise comes from American belief in the power of capitalism.
Canada's business environment is similarly a mix of capitalism and government regulation of business. The significant differences between business environments in Canada and the United States are those of strength in technology, work force, and size of economy, as measured by Gross National Income (GNI); the US is ranked first and Canada eighth (NationMaster.com 2003-2019).
https://hbr.org/2009/07/government-in-your-business

https://www.nationmaster.com/country-info/compare/Canada/United-States/Economy

It is the erosion of the status and bargaining power of private-sector labor unions that has driven a corresponding decline of the social status and economic power of the once-vaunted middle class as the foundation of American prosperity. While some labor unions still have considerable political influence, contemporary corporate business models take advantage of the US government's absence of hands-on involvement in both organized labor and corporate governance. Unlike Canada's socialist model, no level of government in the US can mandate hiring practices for the benefit of organized labor, and in fact, it is a common principle of conservative politics to regard strong organized national labor as an economic cost rather than a benefit and as a "socialistic" threat to free market capitalism. As a result, the continued growth of the mammoth American service sector economy is modeled on part-time, temporary, low-wage, non-employee benefit positions in which service vendors are hired by corporations as independent contractors, which provides enormous relief, from corporate payroll taxes.
The tax issue is another key difference between the US and Canadian systems, and like the labor factor, another advantage for American corporations or others doing business in the US. The economies of the different states vary, as with the Canadian provinces, but there are no federal mandates requiring minimum wage, full-time or permanent employment or employee benefits, and indeed many states have done even more to create condition more attractive to intentional investment like tax breaks, easing environmental restrictions and "right to work" hiring which lifts the requirements in some factories that required employers to maintain a closed union shop. These examples are part of a process of modern economic development known as the so-called "race to the bottom" in which "organic" economic value is extracted from the local region and passed to the corporation which is not a member of that community, and while it is not unique to the US, the Canadian system has much stricter regulation over more of the national economy with much less political and social division as to common expectations , with private sector interests having a much less outsize influence over government economic and financial policy.
Fortunately for Canadian businesses looking to outsource a service operation, especially in a rural or economically depressed area such as the northeastern US/Canadian border region, the combination of abundant low-wage contract labor with other state or local financial incentives make the idea a viable, attractive one.

The American business environment is very similar to Canada's. They are both trading partners and work closely with each other in many industries.
Business in America is covered by all three levels of government: federal, state, and local. This means that all three levels have to comply with federal laws and regulations, and all legislation that is passed on the federal level is therefore applied to every state and locality. For example, U.S Supreme Court decisions must be followed by everyone, however state rulings must only be followed by the state. This creates very different laws, regulations, and work environments in each state and region. In contrast, Canada has only provincial and federal jurisdictions. The federal government is limited in what they can apply to each province, therefore there is not much overlap.
Workers in the United States are restricted more in their rights to unionize. This is partly due to each state law being different. Some states in the U.S have strict requirements for unions, and often try to prevent the right to unionize. In U.S law, when a business is sold, they don't necessarily the guarantee the continued right to collective bargaining, however in Canada this right is carried over. Lastly, in Canada the unions are protected under the Charter of Rights and Freedoms, whereas in the U.S constitution protection is very limited.
Because of the highly capitalistic nature in the country, the U.S leans towards business rights more than the rights of the employees. This is not to say that Canada does not. However, Canada is seen to have better worker protections. Both governments have intervened in their respective business spheres. The U.S applies federal laws to all states and localities, and often the Court hears cases pertaining to employment laws.

The economic system in the United States is mixed. It embraces both socialism and capitalism in that private assets are safeguarded and people are given some degree of economic freedom. Conversely, the economic system encourages government intervention in economic affairs to meet social goals. For this reason, the government can impose restrictions in both public and private economic sectors. Canada’s economic system is similar to that of the US in that it is market-oriented and allows government regulation.
The US government plays various roles when it comes to conducting business. It authorizes different entities to run businesses. Businesses are required to register with the relevant authorities before they begin operations. Similarly, businesses in Canada must register with the relevant provincial authorities.