What details in the first paragraph help establish the atmosphere or mood of "The Sniper" by Liam O'Flaherty?

Liam O’Flaherty establishes the tense, ominous, violent mood of the story in the first paragraph by describing the atmosphere of Dublin under siege during the Irish Civil War. O'Flaherty depicts the twilight sky, which corresponds to the dark, dangerous conditions in the "beleaguered Four Courts" as the Republicans and Free Staters engage in battle. The dim atmosphere and continuous sound of artillery fire throughout the city also adds to the suspenseful, threatening atmosphere of Dublin.
As the night sky darkens and the waters of the Liffey become black, enemy soldiers shoot at one another while night gradually approaches. O'Flaherty's ominous mood is fitting for a short story focusing on the Irish Civil War. Throughout the short story, O'Flaherty explores the effects of the civil war on Irish citizens, soldiers, and family members. In the first paragraph, O'Flaherty establishes a suspenseful, ominous mood, which correlates to the dark, gloomy atmosphere of the beleaguered city during the Irish Civil War.

Let's start with the mood and atmosphere of the story as a whole.  I would say that this story's mood is tense, dark, and violent.  In a nutshell, the story is about a sniper that coldly shoots and kills three people.  One of them happens to be his brother.  
The opening paragraph helps to establish that mood by setting the story in the evening.  Day is fading into night, so there is an actual darkness that accompanies the emotional darkness of the story.  

The long June twilight faded into night. Dublin lay enveloped in darkness but for the dim light of the moon that shone through fleecy clouds, casting a pale light as of approaching dawn over the streets and the dark waters of the Liffey.

Notice all of the words that focus reader attention on darkness and dark times.  "Twilight," "faded," "night," "darkness," "dim," and "pale" all highlight an ominous and oppressive feeling.  The rest of the opening paragraph points readers toward the violence that is happening around the setting.  A civil war is going on and guns can be constantly heard.  Based on the opening paragraph, readers know that this story is going to be a dark and violent story. 

Intermediate Algebra, Chapter 4, 4.1, Section 4.1, Problem 32

Solve the system $\begin{equation}
\begin{aligned}

& \frac{1}{4}x - \frac{1}{5}y = 9
\\
\\
& 5x - y = 0


\end{aligned}
\end{equation}
$ by substitution. If the system is inconsistent or has dependent equations.

We solve $y$ in equation 2


$
\begin{equation}
\begin{aligned}

5x - y =& 0
&& \text{Given equation}
\\
-y =& -5x
&& \text{Subtract each side by $5x$}
\\
y =& 5x
&& \text{Multiply each side by $-1$}

\end{aligned}
\end{equation}
$


Since equation 2 is solved for $y$, we substitute $5x$ for $y$ in equation 1.


$
\begin{equation}
\begin{aligned}

\frac{1}{4}x - \frac{1}{5} (5x) =& 9
&& \text{Substitute } y = 5x
\\
\\
\frac{1}{4}x - x =& 9
&& \text{Multiply}
\\
\\
x - 4x =& 36
&& \text{Multiply each side by $4$}
\\
\\
-3x =& 36
&& \text{Combine like terms}
\\
x =& -12
&& \text{Divide each side by $-3$}

\end{aligned}
\end{equation}
$


We found $x$. Now we solve for $y$ in equation 2.


$
\begin{equation}
\begin{aligned}

y =& 5(-12)
&& \text{Substitute } x = -12
\\
y =& -60
&& \text{Multiply}


\end{aligned}
\end{equation}
$

Provide specific examples in Chapter 8 to explain Diamond's argument that the people who lived in a specific area did not determine how successful domestic agriculture would be in that area.

In Chapter 8, Diamond explains that while there are over 200,000 species of wild flowering plants, very few of them are fit for crop development. He examines three regions--the Fertile Crescent, New Guinea, and the Eastern U.S. to show that people who lived in a region weren't the major determinants of how successful domestic agriculture was in that area.
The Fertile Crescent became a center of agriculture in part because so many of the crops there are productive in the wild. The germination of their seeds occurred naturally, as soon as people began to cultivate them. In addition, many of the plants in this area are self-pollinating. This situation is very different in Mesoamerica, where there were far fewer domesticated animals to provide meat and where the staple crop, corn, was far more difficult to grow than the crops in the Fertile Crescent. Diamond also mentions New Guinea, where the naturally growing crops were also less productive; the region lacked cereal crops because there were no starting grass crops that grow there naturally. In addition, there were few candidates in the eastern U.S., as Diamond explains, to develop into major crops. Therefore, the people who live in a particular geographic area were not the major determinants of whether domestic agriculture would be successful; instead, the crops that grow there naturally were the major determinants. 

What is the function of language?

Language is a system of communication, so its main function -- its use or purpose -- is semantic: Language is a way to encode a particular meaning in symbols (like words) and transmit this meaning to others.
But people who study language want to take a much deeper look. What different kinds of communicative functions does language serve? And do people use language for other reasons, reasons that have little to do with communicating a specific meanings? Different scholars come up with slightly different lists, but they can agree on these basic points.
1. Language has many functions that derive from the semantic, or meaning-encoding, properties of language . People use language to
communicate facts, opinions, and propositions, including statements about abstract concepts.
       The tree is green. Nature is beautiful.
make requests and ask for specific information;
       Could you please hand me the binoculars? Is that a squirrel in the tree?
issue commands;
       Get down out of the tree!
convey emotions and intentions;
       Your arrogance makes my blood boil.
elicit feelings from others (by writing evocative poetry or prose);
       In the morning glad I see / My foe outstretched beneath the tree.
communicate about things that aren't immediately present (because they are located somewhere else, belong to the past or future, or are products of the imagination).
       I wonder if there are any trees on Mars.
Nonhuman animals have systems of communication that can perform some of these functions. For instance, vervet monkeys have alarm call vocalizations that reference specific predators (one means something like, "I see a snake!"). Bees can tell their companions the location of a distant food source by performing a ritualized "waggle dance." But in general, human language stands out for several things, like its ability to address abstract concepts, the past, the future, and hypothetical situations. These functions may be unique to language.
2. Language also serves several non-semantic functions.
One example is "phatic" language, the "small talk" we use in order to establish a mood or be polite. When people meet and say "How do you do?" they aren't really asking for information. The words are essentially empty placeholders. The speech functions as a polite gesture of greeting.
Another  example is the language we use in formal rituals, as when a Catholic priest officiates at a baptism. Although the words may have meaning relevant to the ritual, the priest isn't speaking them primarily to inform people at the ceremony.

The function of language is communication. In its written, verbal, and bodily performative forms, language communicates information based upon a shared set of symbols. Bodily language is not exclusive to humans, and many non-hominid animals rely on physical gestures and posturing to convey meaning. In humans, bodily language may communicate feeling, greetings, fear, or even complex thoughts, as in Sign Language. Verbal language is the most common form of communication used by humans, but it has the disadvantage of being temporally and spatially bound. Technology can help overcome this boundary by recording verbal information to be played at a later date. Writing has the benefit of being static throughout time and space, but it requires one to be literate to understand the written information.
Language is not limited to communicating factual information—it is also used to express emotion, establish and reaffirm identity, and for imagination.
https://www.britannica.com/topic/language

Single Variable Calculus, Chapter 3, 3.4, Section 3.4, Problem 29

Suppose that $H (\theta) = \theta \sin \theta$, find $H'(\theta)$ and $H''(\theta)$

Solving for $H'(\theta)$


$
\begin{equation}
\begin{aligned}

H'(\theta) =& \theta \frac{d}{d \theta} (\sin \theta) + \sin \theta \frac{d}{d \theta} (\theta)
&& \text{Using Product Rule}
\\
\\
H'(\theta) =& (\theta) (\cos \theta) + (\sin \theta) (1)
&& \text{Simplify the equation}
\\
\\
H'(\theta) =& (\theta) (\cos \theta) + (\sin \theta)
&& \text{}
\\
\\

\end{aligned}
\end{equation}
$



Solving for $H''(\theta)$


$
\begin{equation}
\begin{aligned}

H''(\theta) =& \theta \frac{d}{d \theta} (\cos \theta) + \cos \theta \frac{d}{d \theta} (\theta)+ \frac{d}{d \theta} (\sin \theta)
&& \text{Using Product Rule}
\\
\\
H''(\theta) =& \theta (- \sin \theta) + \cos \theta (1) + \cos \theta
&& \text{Simplify the equation}
\\
\\
H''(\theta) =& - \theta \sin \theta + 2 \cos \theta
&& \text{}
\\
\\

\end{aligned}
\end{equation}
$

Du Bois begins the “forethought” of The Souls of Black Folk by declaring that “the problem of the Twentieth Century is the problem of the color-line." In his first chapter, he shifts the word “problem” so that it applies to himself; he describes how whites will often ask him some variation of the question, “How does it feel to be a problem?” Describe what Du Bois means by each instance of “problem,” being careful to note the difference between the two uses of the word.

In the first mention, the "color-line" is, in context, framed as a social "problem," something to be solved through policy and mutual understanding. In context, DuBois published The Souls of Black Folk at the height of the Progressive Era, when educated men and women turned their talents to come up with institutional solutions to the pressing issues that confronted society. These included such things as alcohol abuse, poor working conditions, crowded inner cities, and many others. Writing in 1903, at the beginning of a new century, DuBois was saying that race relations were the "problem" of the present and the future, and The Souls of Black Folk was an attempt to help people understand the nature of the problem by helping readers learn about African-American identity.
In the first chapter, he uses the word "problem" differently. The question often posed by well-meaning whites is, "what does it feel like to be a problem?" In this sense, DuBois and African-American people are "problems" in the sense that they have, as DuBois writes, a "double-consciousness." They live behind a "veil" that separates them from the world of white Americans. They feel a "twoness...an American, a Negro; two souls, two thoughts, two unreconciled strivings; two warring ideals in one dark body, whose dogged strength alone keeps it from being torn asunder." In this chapter, DuBois uses "problem" in this sense—a unreconciled search for "true self-consciousness" that exists in the minds of African-American men and women.
https://www.gutenberg.org/files/408/408-h/408-h.htm

Du Bois' use of the term "problem" highlights what he sees as the unique duality of Black subjectivity in America. The "problem of the color line," as he puts it in his Forethought section, alludes to a particular set of socioeconomic and political issues that stem from the history of Black people in America, particularly the legacy of slavery and the failure of emacipation to address basic inequities. When Du Bois shifts, in the first chapter, to thinking of himself as a "problem," he is describing the sense of alienation Black people feel personally as a result of that history. Du Bois feels, even in grade school, that others see him not as an individual, but as part of the larger "problem" of race. As a result, he comes to evaluate his own individuality in terms of his relationship to that problem. As Du Bois puts it, "one ever feels his two-ness,—an American, a Negro; two souls, two thoughts, two unreconciled strivings; two warring ideals in one dark body, whose dogged strength alone keeps it from being torn asunder."

There is a difference between the personal sense or perception of being a "problem," as expressed in Chapter 1: Of Our Spiritual Strivings, and the "problem of the color-line," as mentioned in Chapter 2: Of the Dawn of Freedom. However, the former condition was precipitated by the latter. DuBois's sense of being a "problem"—a notion that is imposed on him by the liberal, well-meaning whites he alludes to in his prose—is a result of the history that he describes in the second chapter, which constructed black people, first, as non-citizens and "three-fifths" of a person, then, a system that imposed a second-class status and eliminated due process.
Being unwanted, being a "problem," can result in a feeling of defeat or, in the case of DuBois, in a determination to strive: "That sky was bluest when I could beat my mates at examination-time, or beat them at a foot-race, or even beat their stringy heads." Still, the historical framework that constructed him as a "problem" causes that striving to be for naught in many instances: "Alas, with the years all this fine contempt began to fade; for the worlds I longed for, and all their dazzling opportunities, were theirs, not mine."
The perception of DuBois and other black people as a "problem" prevents whites, based on his anecdotes, from speaking to black people as individuals. Instead, black people are spoken to within the context of their racial oppression, from the understanding of their position as members of a permanent underclass. Thus, the "problem" of one's existence as a black person is created by the conditions of history and reinforced even by those who mean well.
https://www.bartleby.com/114/index.html

Students of accounting sometimes suggest that teaching more courses in ethics will produce more ethical behavior in accounting. Do you believe this suggestion has merit?

Studies, such as the one by Johnson, McGuire, and Cooper (2016) cited below, show that teaching ethics as part of undergraduate business courses has a limited effect on students' responses to situations that involve ethics. Though ethics courses have become commonplace in business studies, they have been shown to have limited effects.
The effectiveness of an ethics curriculum in fields such as accounting may depend on several factors. First, the leaders of the university must model ethical behavior for students, and, second, the consideration of ethics has to be present not only in the ethics class, but in every class. Students in accounting should not regard ethics as its own field, but rather as a way of thinking and behaving that has implications in every field. If ethics is made just part of one course, students will not learn to apply ethical decision-making to their work and practice in the field of accounting.
Source:
Jonson, Elizabeth Prior; McGuire, Linda; Cooper, Brian (2016). Does Teaching Ethics Do Any Good? Education & Training, v58 n4, 439-454.