I want to ask a beginner s question I m a beginner, I have a question, please answer it to a master

If you really want to pursue a career in astronomy in the future, the biggest piece of advice I can give you at this stage is to study math and physics. These two disciplines are the foundation of astronomy, don't underestimate the knowledge of high school, you can't build a tall building without a foundation. However, schools with astronomy majors are all excellent schools in the country.

At present, only Nanjing University, Peking University, University of Science and Technology of China and Beijing Normal University have astronomy majors at the undergraduate level. And these schools require good grades to get in. Let's do our best.

Also, if you really plan to pursue a career in astronomy, you should be mentally prepared. It's hard to get a foothold in this field without a Ph.D. The results of astronomy are not as applicable as those of other professions, so we must be prepared for hard work.

If you can't be a professional, it's also a good choice to be a hardcore enthusiast. The books you read are helpful for the theory of cosmology, but I suggest that you still get in touch with some basic things, learn how to identify constellations, use astronomical telescopes, learn the basics of astronomy, and so on. An astronomy enthusiast who doesn't know the stars is not a true enthusiast.

I recommend you take a look at the Astronomy Amateur's Handbook, which is a great book for beginners.

Overall, your time is already tight at the moment, and if you want to make the most of it, the first thing is that you can't fall behind in the school curriculum, so that you have enough energy. And you must have outstanding grades to be admitted to the astronomy major. Mathematical physics must be prominent, and these two courses are crucial if you want to pursue a career in astronomy (especially astrophysics or cosmology).

Astronomy requires a solid foundation and a solid foundation in mathematics and physics, so it should not be rushed. It is recommended to start with basic observation and accumulation. It is advisable to subscribe to the magazine "Astronomy Lovers". Beginner-level enthusiasts can check out the Astronomy Amateur's Handbook.

Participate in the school's astronomy club.

See Astronomy Amateur Magazine

Study hard and strive to get into the astronomy department.

Astronomy is an observational science, which focuses on observation, and the spectrum, the interior and composition of stars should be counted as astrophysics. Therefore, to learn astronomy, we must first have enough understanding of the starry sky and observe more (but Beijing. If you read more books and ask questions if you don't understand, you're done.

, where 13% is the tax rate. Generally, 13% is the VAT rate, VAT is an off-price tax, and the tax-included amount on the VAT invoice = selling price + tax amount. For example, if the selling price of the product is 10 000 yuan and the tax rate is 13%, then the tax-inclusive price of the product = 10 000 + 10 000 x 13% = 10 000 x (1 + 13%) = 11 300 (yuan).

First, the three advantages of modern value-added tax are chaotic

1. Simplification of the tax system.

1) Simplified taxation, which transforms the traditional tax system on goods and services due to multiple taxes into a unified and simple tax structure.

2) Computational simplification, which transforms the complex calculation method linked to the cost into a simple and accurate calculation method that is separated from the cost.

3) Tax rate simplification, which converts the multi-tax rate structure into a single tax rate structure, which greatly reduces the complexity of the tax system caused by the division of multiple tax rates.

2. Strict mechanism.

1) The right to levy VAT and the right to deduct tax are not infringed upon by law. In this way, the coherence, rigor and integrity of the VAT operation mechanism are guaranteed.

2) Through the establishment of an effective management system for VAT taxpayers, all taxpayers are included in the scope of management according to law.

3) In accordance with the requirements of the state, standardize the tax-related content of the commercial invoice, so that the commercial invoice has the function of tax security, so that the tax collection and tax deduction are based on the legal voucher.

3. Easy to manage.

1) The elimination of the complexity of the management system caused by the complex structure of the tax system, "multiple taxes, multiple management, and multiple levies" and the cumbersome collection procedures caused by it.

2) Minimize the workload of collection and the contradiction of the relationship between collection.

3) Due to the unification of the tax policy of goods and services tax, the contradiction in the collection and management caused by the uncoordinated relationship between the collection and collection of goods and services has been reduced.

Second, the eight characteristics of modern value-added tax

1. The scope of VAT covers the whole field of commodity business.

2. There is a coherent, strict and complete operation mechanism for tax collection and withholding.

3. A new type of tax collection relationship has been established in which the taxpayer is not the taxpayer.

4. A new tax calculation method has been formed that separates tax from enterprise cost accounting.

5. Implement a single (excluding zero-rated) VAT rate structure.

6. Implement a tax refund system in which the full amount of imports is taxed in line with WTO rules and the export tax rate is zero.

7. Implement an effective management system for VAT taxpayers.

8. An effective tax invoice system is stipulated for taxpayers.

From the known e 2=c 2 a 2=(a 2-b 2) a 2=1 roll hole 2 ,-1).

Substituting x=c into the elliptic square areal range, we get y 2=b 2*(1-c 2 a 2)=b 4 a 2 , so y=b 2 a, then 2y=2b 2 a= 2 ,-2)

A 2=2 and b 2=1 can be solved by commuffing the previous two equations, so the standard equation for an ellipse is x 2 2 + y 2=1 .

A, B, C three parameters, a total of 3 equations, can be solved.