1 circle is inscribed with quadrilateral ABCD, AB= 1, BC=2, CD=3, and DA=4. Find the radius of a circle.
It is known that an infinite arithmetic progression has three terms: 13, 25, 4 1. Verification: 2009 is a project in the series.
3 Is there a real number X that makes tanx+ (root 3) and cotx+ (root 3) rational numbers?
4 it is known that there is acosx+bcos2x > for any x; =- 1 holds, and find the maximum value of a+b.
In an exam, 333 students answered 1000 questions correctly. Answering below 3 questions correctly means failing, and above 6 questions means being excellent. Which is more, failure or Excellence?
Second, language.
1. There are many misinterpretations of idioms in life. For example, "live like a year" means "live comfortably, like Chinese New Year". Please write two similar distortions to satirize this phenomenon.
2. Analyze the following two sentences:
We all have a family named China.
(2) Blank blue and white strokes (no punctuation)
3. Couplets
Boya Tower was formerly Boya (Boya Tower is a famous building in Peking University).
4. Translation of ancient Chinese (without punctuation)
Wu's wife had a lot of clothes, and dozens of clothes attacked. It was very easy at that time. She lives in a stolen country and steals saliva, but she feels that she is still showing off her embroidery under the jungle. On the theft, I blame this woman for knowing her clothes but not her affairs, and why she put her husband in the recommended gentry's house. The door is not tightly closed. The thief only takes it when she is about to steal it, but she shows off her clothes. She died because talented people in the world didn't care about her clothes and she was stealing them.
5. Reading comprehension is an article selected from Lu Xun's Wild Grass, which requires pointing out the symbolic meanings of many images.
beggar
I walked along the peeling high wall and stepped on the loose dust. There are several others, each of whom is walking. The breeze rises,
The branches of the big tree exposed on the wall shook my head with leaves that had not dried up.
The breeze rises and there is dust everywhere.
A child begged me to wear a jacket, not necessarily sad, close to child's play; I'm tired of his chase.
Mourn.
I walk. In addition, several people left separately. The breeze rises and there is dust everywhere.
A child begged me to wear a jacket, too, not necessarily sad, but dumb, and put it on with open hands.
Potential.
I hate his gestures. Besides, he may not be dumb, it's just a way of begging.
I don't give, I don't have the heart to give, but I am above the giver, and what I give is boredom, suspicion and hatred.
I walked along the broken mud wall, and the broken bricks piled up in the cracks of the wall. There is nothing in the wall. The breeze sends autumn.
The cold penetrated my jacket; There is dust all around.
I thought about how I would beg: in my voice, in what tone? Play dumb. How do you make gestures? ……
In addition, several people left separately.
I can't get paid, and I can't get the heart to pay; I'll become bored and suspicious,
Hate
I will beg with inaction and silence! ……
I'll at least get nothingness.
The breeze rises and there is dust everywhere. In addition, several people left separately.
Dust, dust, ...
……
dust ...
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6. Composition (40 points):
Some corrupt elements believe that corruption is a "universal nature" that everyone can't avoid. It helps to stimulate consumption, enhance feelings, is conducive to economic growth and is harmless to a harmonious society.
Please write to refute the view that "corruption is harmless", and ask for at least five correct quotations from ancient poems and 800 words for your own topic.
Four physics
1 has two cuboids, one is large and the other is small, the bottom area is equal, the height is H 1, H2, and the density is p 1, p2. Stack them together and put them in a liquid with a density of p0. Small and big, small in the world, just not too big. If it is small and large, at the beginning, make the liquid level not too small. In what direction does the big one move at the moment of release, and what is the acceleration a (only expressed by H 1, H2, g)?
On the smooth bottom, there is a big drum with a cover, and the side is a square with a side length of 2d, and there is a small drum without a cover, and the side is a square with a side length of D. The two drums are connected by rods, with a total mass of M. A monkey with a mass of M jumps out horizontally to the right at the rightmost end of the drum, just passing the left end of the small drum and falling in the middle of the small drum.
(1) Find the time from the barrel edge to the center of the barrel.
(2) Find the length L of the rod
(3) Find the speed Vm of the monkey jumping out of the jar horizontally.
3( 1) A ball with a mass of m 1, m2 collides elastically at the speed of v 10, v20, and the collision speed is v 1, v2. Find v 1, v2.
(2) On the left side of the circular track with radius r, there are two small balls with the same mass m, the upper ball speed is 3V0, the lower ball speed is V0, and there is a large static ball with mass 2m at the right end. All collisions are called elastic collisions. Find the elapsed time when the three balls return to their current motion state and position for the first time.
What is the internal energy of an object?
Microscopically, what is the pressure of gas on the container wall?
PVT, what's the relationship? T remains the same, V decreases, how does P change, and how does U change? V remains the same, T increases, how does P change, and how does U change?
Five electrical problems
6 Two squares have a common side, and the resistance of each side is R. Find the equivalent resistance from the lower left corner to the upper right corner.
Seven questions about atomic physics
Five chemistry
1 Fill in the blanks
(1)NaCl solution contains Mg2+(NaOH), SO42-(BaCl2), Ca2+(Na2CO3) and other impurity ions. The reagents for removing impurities are in brackets, and the sequence of adding reagents is as follows.
(2) Electrolytically melting LiCl to obtain Li and Cl2. 1mol will it? The solution of L- 1LiCl was heated and evaporated to dryness to obtain a solid. When the solid is melted by electrolysis, the anode does not produce Cl2. Why?
(3) Why can 3)Ag replace the hydrogen in HI(aq) and H2S(aq)?
(4) Give a simple structural formula of a substance and write an equation for synthesizing nylon -6.
(5) Give the simple structure of monomer and write the simple structure of melamine. Write the equation of synthesizing melamine from urea.
(6) Given the heat of solution of NaCl, the energy change of Na into ions and the energy change of Cl into ions, what can be drawn from the data?
(7) It is known that the decomposition of NH4A(A is an acid radical) is proton transfer. If A is an oxidizing acid radical, redox reaction will occur during decomposition. Try to write down the decomposition equations of NH4NO2, NH4Cr2O7 and NH4MnO4.
2 short answer questions
(1) Add enough Zn to 1mol? L- 1 in HCl and HAc solution. It shows that the rate of hydrogen release is different, and the amount of hydrogen released is also different.
(2) introducing SO2 into Na2S and Na2CO3 solutions to prepare Na2S2O3? 5H2O， 1。 After a period of time, precipitation occurs; 2. Continue to introduce SO2 until the solution is clear; 3. Introduce SO2 again to generate precipitate; Heating, concentrating, cooling, crystallizing and filtering to obtain Na2S2O3? 5H2O .
1 Write the equation of each reaction step.
What is the molar ratio of Na2S to Na2CO3 in the original solution, which is suitable for generating Na2S2O3? 5H2O
(3) AgNO3 _ 3 was dripped into Na2HPO4 solution to form yellow precipitate. Ag3PO4 and Ag2HPO4 precipitates are known to be yellow, and the composition of the precipitates is tested by (ordinary) experimental methods.
④ 1 Write the simple structure of H2O.
Write down the characteristics of H2O as a solvent.
Write the chemical equations of two different types of reactions with H2O.