Who knows the answer to If there is no dust 100 points in class

If there is no dust, the strong sunlight will not really open your eyes.

Everything in the world is wet.

Dust is a fine dry powder of soil or other substances, which is reduced to a fine part of something; Fine powders, dust particles are generally between hundredths of a millimeter and a few hundredths of a millimeter in diameter, which are invisible to the human eye.

Dust is the enemy of human health, so people especially hate it because it carries many bacteria, viruses and insect eggs everywhere and spreads diseases. Industrial dust and fine dust can make workers suffer from a variety of difficult occupational diseases, excessive dust can also cause environmental pollution, affect people's normal life and work, induce human respiratory diseases and so on.

However, the credit of dust must not be erased. If there is no dust in the atmosphere, the sunlight will not be absorbed, reflected, scattered and refracted, and the sky will be white, without wind, snow, rain, dew, glow, and rainbows. Since dust is a hygroscopic particle, without its core, the water vapor in the air cannot condense, and it is difficult for clouds in the sky to form, and the surface of the earth will become arid and barren without the cover of clouds, and the weather will either be too hot or too cold.

Without dust, many harmful rays in the universe would break into the Earth's surface unhindered and pose a deadly threat to humans and various living beings.

In addition to these benefits, dust condenses water vapor. Let them become droplets, or everything will be wet.

Although dust has many problems, its contribution is immeasurable, it can enable the earth to gently obtain the sun's energy, and it can also make the atmosphere have enough condensation nuclei to increase the chance of cloud and rain formation; Regulate the temperature of the earth's surface to make it suitable for the survival and reproduction of life.

Dust is very harmful to the computer, too much dust may block the CPU fan, make the fan stop, cause the CPU to overheat and burn the consequences, but also affect the contact between the boards, and may also cause corrosion of the circuit board.

1.Appropriately fill in the words "scatter" and "reflection" in the horizontal line of the second natural paragraph.

a b2.Second, what do the two dotted "they" in nature refer to?

they" means. they" means.

3.The order in which this article is explained is:

a.Chronological order bLogical order cSpatial order dSequence of procedures.

4.What is the method of explanation for each of the underlined sentences in the text?

5."Dust is mostly hygroscopic. This sentence is taken from the text, and you think it should be put back at the beginning of the paragraph?

A: 7Can the dotted words be removed from the following sentences, and why?

Even some things that people regard as "waste" often have their existence value that cannot be ignored.

Reflection bScatter.

2.refers to "soil and rocks"; refers to "these and other organic particles." ”

4.Column numbers, compare 5Fifth natural paragraph.

6.If there is no dust in the atmosphere, the strong sunlight will make it impossible to open the eyes, if there is no dust in the atmosphere, the sky will become white, if there is no dust in the air, how monotonous nature is! If there were no dust in the air, everything on the ground would be wet, and if there was no dust in the air, there would be less and less water on the earth, and eventually it would dry up completely, and living things would not be able to survive.

7."Often" is the majority of the meaning in the text, and if "often" is deleted, it will become the meaning that all things that are regarded as waste have their existence value that cannot be ignored.

8.Everything has two sides.

Features: Small, annoying, inseparable from the life of people who want to leak out.

Function: 1) They absorb and collect part of the sun's rays while reflecting the rays around. The sunlight is reflected off the dust and becomes soft.

2) It is easy to reflect the purple, blue, and cyan light with a short light wave, and likes to absorb other colors of light with a longer light wave. Due to the higher levels of dust in the lower atmosphere, the sky we see on the ground is blue.

3) Most of the dust has hygroscopic properties. The water vapor in the air must adhere to the dust in order to condense into small water droplets. In this way, when the water vapor in the air reaches saturation, the dispersed water vapor adheres to the dust and forms stable water droplets, which can float in the air for a long time.

If there were no dust in the air, everything on the ground would be wet. In addition, due to the refraction of sunlight by these small water droplets, there will be natural scenery such as sunset and sunset, idle clouds and mist, rainbow and sunset.

4) Tell us that everything has its two sides, and even some things that are regarded as "waste of the stove" often have their existence value that cannot be ignored. Only by correctly understanding them can we pursue advantages and avoid disadvantages and benefit mankind.

If there is no dust in the atmosphere, there is only the scattering of sunlight by gases.

The author uses hypotheses, column figures, comparisons and other methods to clearly and vividly illustrate the inseparable relationship between dust and human beings.

This article introduces us to a lesser-known side of dust: in the eyes of people, it is often the main culprit in polluting the environment, spreading germs, and endangering human health. However, human beings cannot live without dust.

If there is no dust in the atmosphere, strong sunlight will make it impossible to open one's eyes; If there is no dust in the atmosphere, the sky will always be blue.

If there is no dust in the air, everything on the ground will be wet, and more seriously, the relative humidity in the atmosphere will continue to rise, which will affect the survival of living things. In addition, without dust, nature would be very monotonous.

The full text consists of 6 natural paragraphs, which are clearly hierarchical and well-organized. The first paragraph begins with people's common understanding of dust, pointing out the dangers of dust, and then the second natural paragraph uses questions to raise doubts, which is thought-provoking and naturally leads to the following. Paragraph 3 provides a brief description of the size and main ** of the dust.

Paragraphs 4 to 6 detail the characteristics and role of dust from different perspectives.

The sixth natural section is the key section, starting from the characteristic that "most dust has hygroscopic properties", and advancing layer by layer, explaining the important role of dust. In addition, the structure of these three natural paragraphs has a common feature, which is that they first introduce the characteristics of dust, then specify the role of dust, and use the sentence form "if there is no dust" at the end to emphasize and summarize their important role.

This article starts with the understanding of dust and points out the dangers of dust. Then the pen turned and introduced the characteristics and functions of dust from three aspects: dust has the characteristics of scattering light, which plays a role in weakening sunlight and softening light; Dust has the characteristic of scattering seven-colored light, which plays a role in changing the color of the sky; Dust is hygroscopic, can regulate the climate, the dust after moisture absorption forms small water droplets, and the refraction of small water droplets to sunlight forms a natural scenery with thousands of weather.

The Lord said what would happen without dust, what harm would it do to the human body, and the benefits of dust.