In the catalytic converters fitted to modern cars, carbon monoxide and oxides of nitrogen in the exhaust gas are converted to other substances.

a. i. Why is carbon monoxide removed?

ii. Give one harmful effect of nitrogen dioxide.

b. What is meant by a catalytic reaction?

c. In one reaction in a catalytic converter, nitrogen monoxide (NO) reacts with carbon monoxide to form nitrogen and carbon dioxide. Write a balanced equation for this reaction.

In many of the world’s poorest countries, nearly 50 percent of the population is under 15 years of age. If these people are to help improve the productivity of their economies, they must be trained in modern methods of production. In 2000, just over 4 million of the 8.8 million people of Chad were under 15. Explain why it would be difficult for many of these children to be educated and become productive members of a growing economy.

An old manuscript reveals that a landowner in the time of King Arthur held 3.00 acres of plowed land plus a livestock area of 25.0 perches by 4.00 perches. What was the total area in the more modern unit of square meters? Here, 1 acre is an area of 40 perches by 4 perches, 1 rood is an area of 40 perches by 1 perch, and 1 perch is the length $16.5 \mathrm{ft}$.

As part of the Great Plains of the United States, the topography of the state of Kansas is relatively flat. On the other hand, portions of the state of Colorado are mountainous. Describe how the contour interval and the contour lines might vary on topographic maps of these two states.

Palm oil is one of the world's most versatile raw materials. It is estimated that it is an ingredient in $50 \%$ of all products sold by a typical supermarket. It is used in a wide range of products from margarine, cereals, crisps, sweets and baked goods to soaps, washing powders and cosmetics but it is often listed as just 'vegetable oil'. So, its production benefits customers of these products. In addition, an estimated $1.5$ million small farmers grow the crop in Indonesia, along with about $500000$ people directly employed in the sector in Malaysia, plus those connected with related industries. The governments of these countries have encouraged production as it is a major export for these economies.

However, the industry has a poor image. Palm oil production has led to deforestation with a resulting negative impact on climate change. There has been substantial loss of wildlife habitat, even endangering the orangutan. Palm oil companies have been accused by community groups of driving native people off their land which is then used for palm oil production. Socially responsible businesses, such as KL Kepong in Malaysia, have agreed to an ethical code which aims to make palm oil production 'sustainable' with fair treatment for all local populations affected by it. However, many companies have been accused of breaking the code as there is no strong world body to stop them behaving irresponsibly. In any case, food manufacturers want to maximise profits and final consumers want the cheapest raw materials possible.

Analyse the impact on these two stakeholder groups of a decision by KL Kepong to close one of its palm oil plantations

a. use the technology of your choice to determine the range and sample standard deviation of each of the two data sets. b. compare the two data sets by using your results from part (a). Anthropologists are still trying to unravel the mystery of the origins of the Etruscan empire, a highly advanced Italic civilization formed around the eighth century B.C. in central Italy. Were they native to the Italian peninsula or, as many aspects of their civilization suggest, did they migrate from the East by land or sea? The maximum head breadth, in millimeters, of 70 modern Italian male skulls and that of 84 preserved Etruscan male skulls were analyzed to help researchers decide whether the Etruscans were native to Italy. The resulting data can be found on the WeissStats CD. [SOURCE: N. Barnicot and D. Brothwell, “The Evaluation of Metrical Data in the Comparison of Ancient and Modern Bones.” In Medical Biology and Etruscan Origins, G. Wolstenholme and C. O’Connor, eds., Little, Brown & Co., 1959]

Thomas Jefferson was born in 1743. How old was he when he was elected president of the United States in 1800? (Write an equation and solve the problem.)

Modern jet engines have vanes that are deployed to produce a reverse thrust just after a plane touches down on a runway. The air flow rate through a particular engine is $100 \mathrm{~kg} / \mathrm{s}$, and the combustion gases exit the engine at a speed of $800 \mathrm{~m} / \mathrm{s}$ relative to the engine. The fuel-air ratio is 1 to 40 in this case. Calculate the reverse thrust produced by the vanes for the configuration shown.

Design a problem to help other students better understand how inductors work.

$\textbf{\textcolor{#4257b2}{Mental Math}} \hspace{10pt}$ Determine whether the given number is a solution of the inequality.

$$\begin{array}{lcccc} x < -8 \hspace{25pt} & \textbf{a.}\hspace{10pt}0 \hspace{25pt} & \textbf{b.}\hspace{10pt} -8 \hspace{25pt} & \textbf{c.}\hspace{10pt} -9 \hspace{25pt} & \textbf{d.}\hspace{10pt} -7\\ \end{array}$$

{a) Summarize What was the Monroe Doctrine?

{b) Clarify Problems Would the United States have looked weak if it had jointly issued a warning with Britain? Explain.

Critic's Corner The editors of the Folger Library edition of Julus Caesor point out that Elizabethans "did not have our modern distaste for dictators, ... and they admired forceful and successful leaders like Caesar." Do you see evidence of this admiration in Act One of the play? Would you say that Shakespeare himself admires Julius Caesar? Cite details from Act One to support your opinions.

In 1968, before pollution controls were introduced, over 75 billion gallons of gasoline were used in the United States as a motor fuel. Assume an emission of oxides of nitrogen of 5 grams per vehicle mile and an average mileage of 15 miles per gallon of gasoline. How many kilograms of nitrogen oxides were released into the atmosphere in the United States in 1968?

Indicate whether each of the following statements concerning diabetes and the chemical monitoring of this condition is true or false. a. Diabetes results from having too much insulin in the blood. b. The inability of the body to properly use insulin once it is produced is a cause of diabetes. c. High levels of glucose in urine is a sign of diabetes. d. Modern glucose-monitoring systems directly measure the amount of glucose in the blood.