A school is going to organize 290 students to carry out field investigation. There are 100 pieces of luggage. The school plans to rent two types of luggage: type A and type B

A school is going to organize 290 students to carry out field investigation. There are 100 pieces of luggage. The school plans to rent two types of luggage: type A and type B

(1) if X type a vehicles are rented, then (8-x) type B vehicles are rented, (1 point)
(4 points)
The solution is: 5 ≤ x ≤ 6
That is, there are two car rental schemes:
The first is to rent 5 type a cars and 3 type B cars;
The second is to rent 6 type a cars and 2 type B cars. (6 points)
(2) The cost of the first scheme is 5 × 2000 + 3 × 1800 = 15400 yuan;
The cost of the second scheme is 6 × 2000 + 2 × 1800 = 15600 yuan. (7 points)
The first car rental scheme is more cost-effective. (8 points)

What are the environmental protection and energy saving design features of China Pavilion in 2010 Shanghai World Expo!
I found that the China Pavilion has four points of environmental protection and energy saving design:
1. At the design level of architectural form, strive to achieve the emission reduction and consumption reduction of individual buildings. The national pavilion has a layer upon layer of modeling, forming a natural shading for the lower layer on the upper layer in summer; the outer corridor of the Regional Pavilion is a semi outdoor glass corridor, The passive energy-saving technology will be used to provide thermal insulation in winter and ventilation in summer for the Regional Pavilion. The "China Pavilion Garden" on the roof of the Regional Pavilion will also use ecological agricultural landscape and other technical measures to effectively achieve thermal insulation. These measures will make the China Pavilion save nearly 10% more energy than the national requirements
2. In the aspect of building surface technology, the possibility of application of new environmental and energy technologies should be fully considered. For example, all the windows are made of low-energy double-layer glass, and a large number of solar panels are used on the roof of the National Pavilion, which is expected to make China Pavilion fully self-sufficient in lighting power
The rainwater collection system designed on the roof of the National Pavilion can realize the recycling of rainwater; the small-scale constructed wetland technology is introduced into the water landscape of the south side of the Regional Pavilion and the landscape design of the south side of the Regional Pavilion to provide the ecological landscape for the local environment of the city without a lot of land use by using the self-cleaning ability of the artificial wetland
These are very general. Can you give us a detailed introduction? Thank you
In fact, that is to find some information for my paper, the introduction of energy saving and environmental protection design of China Pavilion is OK! It's China Pavilion!

The "one axis and four Pavilions" - the Expo Axis, the Expo Center, the theme pavilion, the China Pavilion and the Performing Arts Center, are all ready, Tourists from all over the world will have access to the world's latest and most popular energy-saving and environmental protection concepts, such as rainwater recycling, solar energy and wind power, river water and geothermal as the power source of air conditioning, wall thermal insulation and other new technologies, so that you can enjoy the future green life ahead of time
The World Expo adopts circulating water cooling. Speaking of the building energy saving of the World Expo, it is understood that many World Expo buildings are built on the side of the Huangpu River, making full use of the water cooling air conditioning system of the Huangpu River to cool these pavilions. In addition, the roof rainwater collection system is used to recover rainwater, so as to take away the heat from the buildings. During the day, there is no need to use high-power air conditioning
It is reported that the purpose of doing so is to facilitate ventilation and bring sunlight to the house. The second is to make visitors from a foreign land feel at home. Of course, the 30000 square meters of plane greening on the north and South squares and the 7000 square meters of vertical greening on the East and west sides of the outer walls can also keep the wall warm and cool
As for the architectural features and energy-saving highlights of the flying saucer shaped performing arts center, it is understood that after the completion of the Performing Arts Center, the number of auditoriums and the size and shape of the stage can be freely changed according to the performance needs and audience capacity, which is a unique energy-saving function of the Expo buildings, In addition, we can use many environmental protection and energy-saving technologies, such as pneumatic garbage collection system, air-conditioning condensate, program-controlled green space water-saving irrigation system, to cool and clean the performance center and improve the green content of buildings
Xu Zheng, President of the World Expo, once said in an interview with the media: "using the modeling design of buildings to maximize the service of solar energy for mankind is another highlight of the World Expo buildings. For example, the China Pavilion, represented by the outstanding modeling design, has a lot of solar cells on its top and outer walls, Even in summer, you don't have to be afraid. You can use the naturally formed upper layer to shade the lower layer. When the temperature is high in summer, you can use ice storage technology to make ice when the power consumption is low at night, and then release the cold source during the day. At the same time, the first added constructed wetland can realize circular self-cleaning, and the whole venue will be nearly 10% lower than the national energy saving index
The Shanghai World Expo, which will open in May, is less than two months away from its closing. The exhibition contents of the Japan Pavilion, which attach importance to environmental protection, energy conservation and other proposals for the future society, and emphasize the importance of Japan China cooperation, such as artificial breeding of Crested Ibis, are highly praised, The Japanese pavilion, which has been in charge of the front-line command since its opening, was interviewed by Kyodo recently, talking about its evaluation of the World Expo and its ambition for the "final stage"
Before the opening of the World Expo, I didn't expect that it would be so popular. A survey released about a month ago showed that the popularity of pavilions in various countries before the Expo was ranked as China, the United States and Japan. But after the Expo, it was China, Saudi Arabia and Japan
In terms of content, China has integrated its own technology and overseas technology. Saudi Arabia uses abundant oil funds to buy foreign technology, while Japan is 100% domestic technology. Saudi Arabia attaches importance to entertainment, while Japan puts forward such themes as environmental protection and energy conservation, Japan China cooperation, etc, However, the Japanese pavilion has been highly praised by the media and VIP

During the 2010 Shanghai World Expo, a supermarket found that the mascot - "Haibao" sold an average of 20 sets a day
The profit is 40 yuan per piece and 4 yuan per reduction. On average, 8 more units can be sold every day. If you want to make a profit of 1200 yuan, how much should you reduce the price per set?

Analysis:
Suppose that the price of each set is reduced by X Yuan, then more than 2x sets will be sold. According to expanding sales volume, increasing profits and reducing inventory as soon as possible, the daily profit of selling mascots is 1200 yuan, which can be solved by equation
Set a price reduction of X yuan per set,
According to the meaning of the title:
（40-x）（20+2x）=1200
That is, 2x & # 178; - 60x + 400 = 0,
∴x²-30x+200=0,
∴（x-10）（x-20）=0,
The solution is: x = 10 or x = 20
In order to reduce inventory, so x = 20
A: the price should be reduced by 20 yuan per set

How many people visited the Shanghai World Expo

The number of visitors to the Shanghai World Expo reached a record 73.08 million