13. As shown in the figure, the correct connection mode of lamps L 1 and L2 in parallel circuit is () A. Figure 3 connects A, B, C and EB respectively. Connect a, b and d, EC respectively. Connect a, c and b, ED respectively. Connect a, c and c, E 14. They are. When only one switch is closed, the light bulb glows and the electric bell does not ring; When only the other switch is closed, the bell rings and the light bulb does not light up. If the circuit works and the light bulb and the electric bell do not affect each other, then when both switches are turned off, the possible situations are () A. The electric bell rings, the light bulb lights B. The electric bell rings, the light bulb doesn't light C. The electric bell doesn't ring, the light bulb lights D. The electric bell doesn't ring, and the light bulb doesn't light 15. Xiao Ming should have used "-"and "3" when using the electric meter. The result of this will be (a) the rotation angle of the ammeter pointer becomes smaller; B. The ammeter pointer becomes larger, and the ammeter may burn out; C. the ammeter pointer does not move; D. the ammeter pointer is reversely deflected; 2. Fill in the blanks 16. "Deafening" embodies the _ _ of sound, and "harsh voice" embodies the _ _ of sound. 17. use a laser rangefinder to launch a laser beam to the moon. The laser beam propagates between the earth's atmosphere and the moon along _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The reason why astronauts can't be heard directly by their companions on the moon is _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. 18 there is a device called "wet and dry thermometer" which can reflect the water vapor content in the air. It consists of two identical thermometers side by side, one of which is wrapped in a wet cloth. This is because the water in the wet cloth absorbs heat At a certain temperature, the smaller the reading difference between the two thermometers, the wetter the air. 19. The calibration part of an ordinary thermometer is a triangular body, and the cross section is shown in the figure. In this way, we can see the extremely fine mercury column in the thermometer for reading. This is because the curved glass is equivalent to _ _ _ _ _ _, so that we can see the magnified image of mercury column. 20. The classmate whose height is 1.60 m stands 3m in front of the flat mirror. He looks like _ _ _ _ _ m in the flat mirror. Another classmate finds that the ammeter pointer is biased to the right where there is no scale, because. Third, drawing questions
22.( 1) As shown in the figure, please draw the refracted light after the incident light passes through the convex lens; (2) As shown in the figure, when a person stands on the river bank, his eyes B can just see the spire A' reflected in the water on the other side. Please draw the path of reflected light. fire fighting
23. As shown in Figure 7, I will give you two dry batteries, a switch, two small bulbs, two ammeters and several wires. Please design an experimental circuit: two small bulbs are required in parallel. One ammeter measures the current in the main circuit, and the other ammeter measures the current in the branch circuit. The switch controls the switch of two light bulbs at the same time. Draw a circuit diagram 2. According to the circuit diagram you designed, connect the following circuit elements into the physical circuit.
Fourth, experimental exploration 24. The following table is the experimental data recorded by a classmate while exploring the solidification law of a substance. Please complete the following questions as required. Time/m2 minl1.522.533.544.555.566.5 Temperature/℃ (optional: solid, liquid or gas); (2) According to the data in the table, it can be judged that the substance is _ _ _ _ _ _. (optional: "crystalline" or "amorphous"); (3) According to the data in the table, it can be judged that the freezing point of this substance is _ _ _ _ _ _ _ _℃. 25. In the experiment of "Exploring the imaging characteristics of flat mirror", Xiao Ming experimented with glass plates, the same two chess pieces A and B, a balance, plasticine, white paper and other equipment, as shown in the figure. (1) During the experiment, the glass plate should be placed on a horizontal desktop. (2) The same two pieces A and B are selected for the experimental equipment, with the purpose of _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _; (3) In order to explain whether the image formed in the plane mirror is a real image or a virtual image, the specific operation steps are as follows: put the white paper vertically on the chess piece B, remove the chess piece B, and directly observe the white paper to see if an image can be formed on the white paper; If _ _ _ _ _ _ _ _ _ _ _ _, the image formed by the plane mirror is a virtual image; (4) During the experiment, Xiao Ming moved the glass plate horizontally to the right along the 00' axis (the contact part between the glass plate and the desktop), and it was found that the image in the mirror moved relative to a _ _ _ _ _ (fill in "right", "left" or "no"); He turned the glass plate around the 00' axis and found the image in the mirror _ _ _ _ _ _ (choose "turn to yourself", "turn away from yourself" or "don't move"). 26. When doing the experiment of "Exploring the imaging law of convex lens" with candles, convex lens and light screen: (1) If the candle flame is on the light screen, (2) During the experiment, when the distance between the candle flame and the convex lens is 12cm, move the light screen to a certain position, and then move the candle flame to the right by 5cm. At this time, move the screen to a certain position (fill in "left" or "right") and get _ _ _ _ _ on the screen. 27. Please design a circuit and draw a circuit diagram with the given equipment according to the following requirements. Equipment: a power supply, two switches, an electric bell, a red and green light bulb, and several wires. Requirements: Patient A turns off the switch, the red light is on, and the electric bell rings. Patient B turns off the switch, the green light is on, and the bell rings. Eighth grade first volume math final review examination paper
(Time 100 minutes, total 100 minutes)
First, multiple-choice questions (3 points for each question, a total of 30 points)
The arithmetic square root of 1.4 is ()
A.2b–2c . d . 2
3. Enlarge the three sides of a right triangle by the same multiple, and the triangle is ().
A. acute triangle B. obtuse triangle C. right triangle D. arbitrary triangle
4. Every regular polygon with an internal angle of 120 is ().
A. square b regular pentagon c regular hexagon d regular octagon
5. The regular polygon that can be densely laid separately is ()
A. regular pentagon, regular hexagon, regular heptagon and regular octagon
8. The following is a part of the table of food nutrients (the nutrient content of the edible part per100g of food). In the data composed of grams of carbohydrates provided in the table, the median and mode are () respectively.
Vegetables: mung bean sprouts, Chinese cabbage, rape, cabbage, spinach, leeks and carrots.
Carbohydrate 4 3 4 4 2 4 7
A.4，3 B. 4，4 C. 4，7 D. 2，4
9. It is known that the proportional function y =-kx and the linear function y=kx-2 (x is the independent variable) are images in the same coordinate system.
Roughly ()
A B C D
10. If in △ ABC, AB= 13, AC= 15 and AD= 12, the length of BC is ().
A. 14
Two. Fill in the blanks (3 points for each question, 30 points in total)
1 1. Suppose that the average of the five numbers 7, 4, 3, a and 5 is 5, then a=.
12.p (3,–4) is symmetrical about the origin.
13. It is known that the image of linear function y=kx+b passes through point (0,–5) and is parallel to the image of straight line y= x, then the linear function table.
The expression is.
14. Suppose+| 2x–y | = 0, then x–y =
15. As shown in the figure, the ABCD of the small fish is rhombic, and the known fish length BD=8 and AB=5. Take the straight line where BD is located as the X axis and the straight line where AC is located as the Y axis, and establish a rectangular coordinate system, then the coordinate of point C is.
(Question 15) (Question 16) (Question 20)
16. As shown in the figure, given the isosceles trapezoid ABCD, AD‖BC, AD=5cm, BC= 1 1cm, and the height DE=4cm, then the ladder.
The circumference of the shape is.
18. The area of the triangle enclosed by the straight line y=2x+8 and the coordinate axis is.
20. Fold a rectangular piece of paper as shown. After folding along AE, point D falls on point F on BC side, which is known.
AB=8cm, BC= 10cm, then S△EFC=.
Third,
22.(5 points) Calculation: -2+(- 1) 2.
24.(6 points) As shown in the figure, is it known that in the parallelogram ABCD, E and F are on the diagonal AC, AE=CF, and the quadrilateral EBFD is a parallelogram? Try to explain why.
26.(8 points) As shown in the figure, l 1 represents the relationship between the sales volume of notebook computers in a shopping mall, and l2 represents the relationship between the sales cost and the sales volume of notebook computers in the shopping mall:
(1) When x=2, the sales amount = _ _ ten thousand yuan, the sales cost = _ _ ten thousand yuan and the profit (income-cost) = ten thousand yuan. (3 points)
(2) When a table is sold one day, the sales amount is equal to the sales cost. ( 1)
(3) The corresponding function expression of l1is. (2 points)
(4) Write the functional expression between profit and sales. (2 points) The answer time for the final question of the first volume of the eighth grade biology is 40 minutes, out of 50 points. 1. Choose (15 points, each small question 1 point) 1. When a fish loses its pectoral fin and ventral fin, it will appear () A. It can only sink, but can't float B. It can only float, but can't sink C. The swimming speed slows down. 2. The following characteristics that do not belong to terrestrial animals are () A. Generally, there is a structure to prevent water loss. B. breathe through the body wall. Most of them breathe through the trachea or lungs. Generally speaking, they have developed sensory organs and nervous system. 3. The main basis for classifying whales living in water as mammals is () A. Whales breathe through the lungs. The whale's heart has four cavities. C.the whale's body temperature is constant. Whales are viviparous. 4. Animals can promote the material circulation of the ecosystem. The following statement is wrong: (a) Animals can eat plants directly or indirectly and absorb their own ingredients through digestion. B. Food entering animals is decomposed into carbon dioxide, urine and other substances, releasing energy. The decomposed substances can be absorbed and utilized by plants. Animal remains can be decomposed by decomposers. Release carbon dioxide, nitrogen-containing inorganic salts and other substances. Animals can help plants pollinate and spread seeds. 5. The following descriptions about spores are wrong: (a) Spores are structures used by bacteria to reproduce. Spores are the dormant bodies of bacteria. Spores can germinate bacteria. D. spores are structures formed by bacteria in unfavorable environments. 6. "The drunken butterfly flower is deeply seen. The poem" A little water flies slowly "describes () A. defensive behavior, feeding behavior B. defensive behavior, migratory behavior C. feeding behavior, reproductive behavior D. migratory behavior, reproductive behavior 7. Among the following animal behaviors, () A. Puppies do arithmetic; B. Newborn piglets eat milk; C. Great tits drink milk; D. Dolphins perform heading and jumping; 8. Radar is invented according to the principle of echolocation of animals. This animal is () A. Bat B. Dolphin C. Giraffe D. Tortoise 9. The following foods are made without bacteria and fungi () A. Wine B. Sausage C. Bread D. Sufu 10. The scientist known as the "father of microbiology" is () A. Levinhawk B. Darwin C. Pasteur D. When it comes to moldy objects, dust often flies. The main components of this dust are () A. Dust on objects B. Spores of mold C. Seeds of mold D. Spores of bacteria 12. Snails, anemones and spiders are grouped together, while golden snakes, frogs and sparrows are grouped together. This is based on () A. Whether the spine exists B. Whether the body temperature is constant C. Different fertilization methods D. Different reproductive methods 13. The following areas with the richest biodiversity are () A. Farmland B. City C. Grassland D. Forest 14. The plants called "China pigeon tree" are () A. The highest proportion of biological species in China is () A. Pteridophyte B. Bird C. Fish D. Gymnosperms II. Fill in (16, each grid 1 minute) 16. The motor system of mammals consists of and. 17. using it to produce some substances needed by human beings can save the cost of building factories and purchasing instruments and equipment, and reduce complicated production procedures and. 18. Bacteria are also cells, which are different from animal and plant cells. The main difference is that it has no shape, and most cells can only use existing life. The way bacteria reproduce is reproduction. 19. Tonsillitis, scarlet fever, tinea of hands and feet, rice blast and wheat leaf rust are all caused by some bacteria and fungi. Substances produced by fungi that can kill some pathogenic bacteria are called, after long-term use, bacteria in the human body will produce a certain amount. 20. The content of biodiversity is very rich, which not only refers to the diversity of new species, but also includes the diversity of new species and new species. 2 1. In order to protect biodiversity, people divide certain areas of _ _ or _ _ including protected objects for protection and management, which is _ _. 3. Break (1 each item, 5 points in total) 22. Insects are the only flying animals among invertebrates. () 23. The learning behavior of animals is based on genetic factors. All bacteria and fungi are decomposers in the ecosystem. () 25. In the biological taxonomic unit, "door" is the most basic taxonomic unit. () 26. Many medicinal materials need wild animals as raw materials. () Fourth, Lian Yilian (4 points) 27. Do you care about all kinds of animals around you? Please find out where the following animals live. Red-crowned crane desert ecosystem kangaroo forest ecosystem giant panda wetland ecosystem camel grassland ecosystem 29. (4 points) There are many reasons why biodiversity in China is threatened. Write down the reasons why biodiversity is threatened according to the following information. Data 1 Huaihe River Basin 1994 A serious pollution accident broke out, resulting in the death of Hongze Lake120,000 kg of fish, 90,000 kg of crab and 25,000 kg of shrimp. The famous Beijing-Hangzhou Grand Canal has also been seriously polluted. At present, most cities in southern Jiangsu are dark and smelly, becoming a "dead river" without animals. Data 2 200 years ago, Australia introduced several kinds of rabbits from Europe for people to watch. In a sudden fire, the rabbit escaped from the wooden cage and became a rabbit. In less than 100 years, it has spread all over the Australian mainland, becoming a scourge that destroys crops, competes with cattle and sheep for pasture and affects traffic safety. ? Data 3/kloc-At the beginning of the 9 th century, there were many traveling pigeons in the forests of the eastern United States, which covered the sky when flying in groups, and the number was hundreds of millions. Millions of pigeons are killed every year because of hunting and catching, and the forest is seriously damaged. Most pigeons were ruthlessly killed around 1900 and disappeared from the wild. The last pigeon kept in Cincinnati Zoo in the United States died in 19 14. Data 4 In ancient times, Shang Wang went hunting at the southern foot of Taihang Mountain near Qinyang, Henan Province, and captured seven Asian elephants at a time. However, the vassal States living in this area cut down forests and cultivated farmland on a large scale, and Asian elephants promoted their habitats in the Yellow River basin. From 770 BC to 477 BC, the distribution area of Asian elephants moved to the Huaihe River basin in the south and the middle reaches of Hanshui River in the west. After another thousand years, the northern boundary of the Asian elephant retreated to the south of the Yangtze River, and the eastern end was from southern Zhejiang to northern Fujian. About 1000 years ago, Asian elephants had retreated to Guangdong, Guangxi and Yunnan. At present, Asian elephants only live in the south of Xishuangbanna, Yunnan Province, China, with only over 200 elephants. (1) (2) (3) (4) Reference answer and grading standard 1. Choose one (15, each small question 1 point)1-5cbda6-10cbabc1. Muscle 17. Bioreactor; Environmental pollution 18. Nuclear energy; Organic matter; Split 19. Parasitic; Antibiotics; Resistance 20. Species; Gene; Ecosystem 2 1. Land; Waters; Nature reserve III. Discontinuous (5 points, 65438+ 0 points for each small question) 22. √ 23.√ 24.× 25.× 26.√ Four. Fall in love (4 points, each couple 1 point) 27. Do you care about all kinds of animals around you? Please find out where the following animals live. Red-crowned crane-wetland ecosystem kangaroo-grassland ecosystem panda-forest ecosystem camel-desert ecosystem 5. Think about (10) 29 (1) environmental pollution. Water pollution has led to the death of many aquatic animals, and the species and quantity of organisms have decreased sharply. (2) Invasion of alien species. Rabbits have no natural enemies in Australia, which leads to the expansion of rabbit population, destroys the local ecological balance and endangers local species. (3) Overhunting and indiscriminate killing by human beings led to the extinction of this species. (4) the change of living environment. Deforestation by human beings has destroyed the living environment of Asian elephants. History final volume: /ResourceHtml/846458.html