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Anonymous users2024-02-07The vastness of the universe is beyond people's imagination. Astronomers measure the distance of the universe in the units of:
a Astronomical units.
The basic unit of measuring distance in astronomy. In their daily study work, people come across a huge number and often say, "Ah!
That's an astronomical amount! ”。Truly!
The numbers used in astronomy are often huge, take the sun as an example, the distance between the earth and the sun is 149597870 kilometers, which has 9 as the number, if you use "meters" and "kilometers" as units, then it is too small, it is not easy to write and it is easy to make mistakes. So astronomers use the distance from the sun to the earth as a unit, called the "astronomical unit", as a "ruler" to measure the distance between celestial bodies. Such as:
Pluto is an astronomical unit from the Sun.
If we use kilometers to learn our distant stars, for example, quasars have a distance of 190000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 The propagation speed of light is 300,000 kilometers per second, if you calculate it this way, this quasar is 20 billion light-years away, that is, the light we see is emitted 20 billion years ago!
Astronomers now also use a larger "measuring scale" – the parsec." A 1 parsec is equal to 206265 astronomical unit, or 308568 billion kilometers or light-years.
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Anonymous users2024-02-06Multiple choice question d A light year is the distance that light travels in a year of 9,460.5 billion kilometers.
Multiple choice ad The distance between the Earth and the Sun is 149597870 kilometers as an astronomical unit.
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Anonymous users2024-02-05d It must be, because the teacher just said it recently! You can go to the physics book of the first semester of the second year of junior high school, and I said it when I was learning about the refraction of light!
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Anonymous users2024-02-04Multiple choice choice D, multiple choice choice AD
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Anonymous users2024-02-03Pick D. You're going to do this with elimination.
You must first determine the approximate location of the four points on the way, 1 at 90 degrees of longitude and 25 degrees of latitude; 2 at longitude 45 degrees, latitude 50 degrees; 3 at 90 degrees longitude and 40 degrees at latitude; 4 at longitude 110 degrees, longitude 20 degrees.
Hebei Province is located at 113°04 east longitude'to 119°53', 36°01 N'to 42 ° 37'。
Assuming that the map depicts the Northern Hemisphere, then: latitudes 1 and 4 are already on the Tropic of Capricorn, belong to the tropics, and cannot be the same as the crops in Hebei (temperate zone), so only d is correct in the answer.
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Anonymous users2024-02-02Question 18: Select D
Only the longitude and latitude are given in the figure, and it is impossible to judge the north-south latitude, nor can I judge the east-west longitude, so I can only guess the medium, high, and low latitudes.
Hebei Province is located in the middle latitudes of China, and the corresponding type of agriculture can only be barely guessed.
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Anonymous users2024-02-01It feels like there are few necessary conditions, such as what is this diagram, 1,2,3,4 stands for something like that.
Downstairs makes sense, d is the most likely.
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Anonymous users2024-01-31I should choose D. I estimate that this map is a latitude map, and Hebei is located between 30-60 degrees north latitude, so choose d
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Anonymous users2024-01-30There are no prerequisites, how can it be a diagram?
1) Lhasa is located on the Qinghai-Tibet Plateau, with low latitude, high terrain, thin air, large daily temperature difference, strong solar radiation during the day, which promotes warming, and weak atmospheric inverse radiation at night, which promotes cooling. The annual range is small, in summer, the high altitude makes the temperature low, and in the winter, the low latitude makes the sun not low. So the answer is c. >>>More
It is located in the equatorial windless zone.
The equator is a zone of low pressure, where updrafts prevail, and air flows up and down without producing wind (wind is produced by the horizontal movement of the atmosphere), so the wind is calm. >>>More
The landlord's point of view is too extreme,Of course,The society attaches too much importance to foreign languages and ignores the mother tongue is really worrying,In fact, the English we learn can come in handy,Personally,English learning should be free,Can speak and listen to it,Test-taking things can be less.。。 But on the other hand, the current situation, as you said, everything has to be it, so there is only a point of complaining, at least the current situation is difficult to change, so, since you have to learn, learn to learn well. If you don't have the ability to change, try to adapt.
Under normal circumstances, the tropospheric atmospheric air temperature decreases with altitude, while inversion is an abnormal phenomenon in which the temperature increases while the altitude increases. Therefore, the temperature inversion phenomenon must be lower than the temperature of the bottom layer. >>>More
Add 2G to the memory, and the system will be replaced by a 64-bit one: