Summarize the events at the end of the story. Do you think it is an effective ending? Explain.

When an ending to a story is unclear or uncertain, it's...?

Some people might find this story to be overly brutal or violent What do you think of this story s combination of ironic humor and a shocking ending? Why do you think Gordimer wrote her story this way? compare your responses with those of your classmates and discuss them.

A coin is tossed and a number cube is rolled. What is the probability of heads and a number greater than three?

Describe a dilation with center (0, 0) that would produce an image such that every image point is closer to (0, 0) than its corresponding preimage point.

All members of the junior class at a local high school took the PSAT exam. The distribution of the results of the mathematics section was found to be approximately normal, with a mean score of 52 and a standard deviation of 6.8. Stephan claimed that he scored better than 90% of the students in the junior class. Use z-sore and your z-table to determine what score Stephan must have earned to be correct.

A historian discovers a nineteenth-century notebook in which some observations, dated 1822, were recorded on a substance thought to be a new element. Here are some of the data recorded in the notebook: "Ductile, silver-white, metallic looking. Softer than lead. Unaffected by water. Stable in air. Melting point:

$$153 ^ { \circ } \mathrm { C }$$

Den sity:

$$7.3 \ g/cm^3$$

Electrical conductivity: 20% that of copper. Hardness: About 1 % as hard as iron. When 4.20 g of the unknown is h eated in an excess of oxygen, 5.08 g of a white solid is formed. The solid could be sublimed by heating to over

$$800 ^ { \circ } \mathrm { C }$$

" Using information in the text and the CRC Handbook of Chemistry and Physics, and making allowances for possible variations in numbers from current values, identify the element reported.

Show that the inverse of

$$A=\left[\begin{array}{rr} a&b \\ c&d \end{array}\right]$$

is given by the formula

$$A^{-1}=\left[\begin{array}{rr} \dfrac d{\Delta}& \dfrac {-b}{\Delta} \\\\ \dfrac {-c}{\Delta}&\dfrac {a}{\Delta} \end{array}\right]$$

where $\Delta =ad-bc \neq 0$. The number $\Delta$ is called the determinant of A.

Integrate using the method of trigonometric substitution. Express the final answer in terms of the variable. $\int \frac { d x } { \sqrt { 4 - x ^ { 2 } } }$

For the characteristic function

$$\begin{gather*} s^3 + 5s^2 + 9s + 5 \end{gather*}$$

, use Routh’s stability criterion to determine the number of roots with positive real parts. Confirm your answers by using a computer to find the roots.

Find the limit by interpreting the expression as an appropriate derivative. (a)

$$\lim _ { x \rightarrow 0 } \frac { \ln ( 1 + 3 x ) } { x }$$

, (b)

$$\lim _ { x \rightarrow 0 } \frac { \ln ( 1 - 5 x ) } { x }$$

Independence of events is not always obvious. Toss two balanced coins independently. The four possible combinations of heads and tails in order each have probability 0.25. The events A = head on the first toss B = both tosses have the same outcome may seem intuitively related. Show that P(B|A) = P(B), so that A and B are in fact independent.

The maintenance cost for furnaces at a copper smelting plant have been constant at $140,000 per year for the past 5 years. If the interest rate was 8% per year for the first 3 years and then it increased to 10% in years 4 and 5, what is the equivalent future worth (in year 5) of the maintenance cost? Show hand and spreadsheet solutions.

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