Current location - Training Enrollment Network - Mathematics courses - The 12th Beijing Senior High School Mathematics Knowledge Application Competition Preliminary Competition
The 12th Beijing Senior High School Mathematics Knowledge Application Competition Preliminary Competition
The 12th Beijing Senior High School Mathematics Knowledge Application Competition Preliminary Competition

(Enter your own answers in bold)

One,

Information:

Corn price:

Last month's highest price closed yesterday and the lowest price closed today.

07/ 12 343.6 357.4 347.6 35 1 7.2 2 16 15 578474

08/03 360.6 374 365 367.6 7 7264 179300

08/05 370.6 384 374.6 378.2 7.4 728 49289

08/07 380 393 383.4 387.6 7.6 2003 103636

08/09 386.6 396 392.4 393 6.4 290 16902

08/ 12 393.6 404 397 400.2 6.4 5054 168627

09/03 403.4 4 10 407.2 409.4 6 209 8055

09/05 408.4 4 13.4 4 12 4 13.4 5 22 152

09/07 4 10.6 4 17.4 4 17 4 17 6.4 8 137 1

09/ 12 397 405 400 403 6 38 29246

10/03 402 407 407 407 5 0 355

10/07 408 4 13 4 13 4 13 5 0 16 1

10/ 12 399 406 403 403 4 13 6587

out of:/news/29 1 1724 . html

Corn yield:

In 2008/09, the US corn production data was slightly lowered.

________________________________________

China Food Industry Network (2008-11-2011:00:10)

The corn production in the United States is estimated to be 654.38+02 billion bushels, down 654.38+03 billion bushels from last month and down 8% from last year. According to the crop situation as of June 1 65438+1October1,it is estimated that the yield per mu of corn is 153.8 bushels, which is 0. 1 bushel lower than the previous year, but 2.7 bushels higher. If it is true, it will be the second highest level in history, only lower than in 2004. Corn production will reach the second highest level in history, only lower than last year. The initial inventory and import data remained unchanged, resulting in a stable total supply data of 654.38+03.7 billion bushels, which was lower than the previous year's 654.38+04.4 billion bushels. The target yield data of maize in June 1 65438+1October1showed that the number of ears per mu in each target yield state of 10 reached the highest level in history. The ten states are Illinois, Indiana, Iowa, Kansas, Minnesota, Missouri, Nebraska, Ohio, South Dakota and Wisconsin. Except Kansas, Nebraska and Wisconsin, the number of grains per panicle in other States reached the highest level in history. In 2008/09, the corn consumption data was lowered, because the export data was lowered by 50 million bushels to 654.38+09 billion bushels. Other consumption data of corn remain unchanged. The downward adjustment of export data led to an increase of 36 million bushels in ending inventory data to165438+24 million bushels. The increase in inventory data at the end of the period, the increase in overseas supply, and the continuous decline in spot and futures prices have led to a bleak outlook for corn prices in 2008/09. The average price of corn in 2008/09 is expected to be $4.00 to $4.80 per bushel, compared with a record $4.20 last year.

out of:/money/future/2006 09 27/0000294953 1 . shtml

The Influence of American Energy Law on World Food;

American new energy law has two bright spots. One is to raise the fuel consumption standard of automobiles through legislation, requiring the American automobile industry to increase the fuel consumption of automobiles from the current 27.5 miles per gallon to a new 35 miles (about 15 kilometers per liter) in 2020, which is equivalent to reducing the fuel consumption ratio by 40%. The second is to encourage a substantial increase in the use of biofuel ethanol, and put forward that "by 20 12, the annual use of biofuel ethanol or biofuel should reach 7.5 billion gallons". It is also stipulated that the consumption of biofuel ethanol will reach 36 billion gallons by 2022, and it is also required that 2 1 100 million gallons must be cellulose ethanol, that is, non-grain ethanol made of non-edible fiber. This means that fuel ethanol is mainly non-grain ethanol, which is worthy of recognition.

As we all know, the annual per capita oil consumption of the United States is about 3.28 tons, which is more than 10 times that of China. One of the important reasons why the United States has become a big oil consumer is that there are many cars and a large amount of oil is consumed. Most of the oil consumed in the United States is drunk by cars. The United States is also the largest emitter of greenhouse gases in the world. In 2003, China's per capita carbon dioxide emission was 3.2 tons, India's was 1.2 tons, and the United States was as high as 20 tons. The first "suspect" of greenhouse gas emissions is automobile exhaust. However, the automobile fuel economy index in the United States has not changed for many years. Therefore, for the first time, the United States passed legislation to raise the standard of automobile fuel consumption, which is a key to the energy problem in the United States.

The new energy bill encourages a substantial increase in the use of biofuel ethanol, which is not only conducive to alleviating the oil shortage, but also creates market pressure on oil exporting countries. However, it cannot be ignored that there are still many challenges to achieve this goal.

One of the challenges is that the production of non-grain ethanol requires a lot of raw materials. How to grow enough raw materials without damaging the environment and transport them to the processing plant in an efficient way is a difficult problem. According to American media reports, farmers who deeply feel the rising prices of fuel and fertilizer do not support cellulosic ethanol without reservation. At that time, if there are not enough raw materials for production, a large number of them will be replaced by grain, which may not only stimulate global grain planting, but also lead to world grain shortage and soaring prices.

The second challenge, the transportation of biofuel ethanol, is another difficult problem. In the United States, ethanol is mixed with gasoline, accounting for about 5% of the fuel ratio of American cars, and the ethanol added to each gallon of gasoline does not exceed 10%. An independent, safe and efficient transportation system must be established to transport biofuel ethanol to gas stations scattered all over the country.

The third challenge is that the production of biofuel ethanol consumes a lot of oil and water, which destroys the environment. Moreover, the safe use of ethanol, the cost performance ratio with other conventional energy sources and whether consumers can accept it are all problems, which determines that the market prospect and profit margin of biofuel ethanol are uncertain and the investment risk is too great. If the relevant policies are not in place, bioethanol producers can't meet the challenge, and the fuel price is unbearable for consumers, and the goal of developing non-grain ethanol may fail.

Moreover, according to the goal of using 36 billion gallons of ethanol in 2022, the proportion of ethanol in the national automobile fuel will increase to 22%, which means that the United States needs to manufacture more cars that use 85% ethanol fuel. This goal is also a great challenge for the American automobile industry.

One of the sources of global food price increase is the United States, mainly because the United States has adjusted its fuel ethanol policy, which has greatly reduced the food supply in the world market, produced "price effect" and "substitution effect", and caused food price increase and economic fluctuation. Although the new American bill emphasizes that the raw materials for producing fuel ethanol mainly turn to non-grain plants, the increase of the total amount will inevitably increase the consumption of grain, which will aggravate the negative impact on the world economy and make the food price problem more prominent.

The passage of the new energy bill is a "historic turning point" and a new starting point of American energy policy and strategy. The revision of the American Energy Act has inspired the world's major energy consumers: energy is related to national security and must be regulated by legislation; Efforts to reduce dependence on traditional energy and imports are the inevitable orientation of big countries' energy and environmental strategies.

Out of: /page.php? cid=254

Number of participants in the United States: 600 due to:. com/integrate/other/2007/08/03/3393654 . shtml

Russian participants: 467 from:/Huo Feng/Other/2004-08-23/023289122.html.

Number of participants in Jamaica: 52, because:/question/64913021.html.

1, I think we should use the weighted average method to give these countries a score for each of the gold, silver and bronze medals!

2. China: (51* 3+21* 2+28)/639 = 0.3490.

USA: (36*3+38*2+36)/600=0.3667.

Russia: (23 * 3+21* 2+28)/467 = 0.2976.

United Kingdom: (19 * 3+13 * 2+15)/323 = 0.3034.

Jamaica: (6*3+3*2+2)/52=0.5

So according to my arrangement method:

Jamaica, 1

2. America

3. China

4. Britain, Britain

5. Russia

3. What I gave (1) is to reflect the sports level of a country from the average level of athletes!

I count the gold medal winner as 3 points, the silver medal winner as 2 points, the bronze medal winner as 1 point, and nothing else. Finally, I divided by the total number of participants, and finally got the average score of each athlete!

Apply the mathematical knowledge of "weighted average"

The answer is complete. . . . . .

Should meet your requirements! But it's a little late.