A.B. 2 C. D

2. As shown in the figure, it is a geometry composed of four cubes with the same size, and its front view is ().

A.B. C. D。

3. The correct one in the following categories is ().

A.B. C. D。

4. In the following survey methods, the "general survey" method () should be adopted.

A. Investigate the market share of a certain brand of mobile phone B. Investigate the implementation of low-carbon life of citizens in our city.

C. Research on the Components of the First Fighter 歼 15 China D. Range Investigation of a Certain Type of Shell

In the next three years, China will invest 845 billion yuan to alleviate the problem of "difficult and expensive medical treatment".

It is expressed as () by scientific notation.

A.845×1400 million yuan B.845×1300 million yuan C.845×1400 million yuan D.84.5×1200 million yuan.

6. In order to know the age of 2000 athletes who participated in the sports meeting, 100 athletes were randomly selected.

For this problem, the following statement is correct ().

A.2000 athletes are the whole B, and each athlete is an individual.

C. 100 athletes is a sample. D. 100 athletes' age as a sample.

7. Calculation is equal to ().

A.B. C. D。

8. If x2-x-m = (x-m) (x+ 1) and x≠0, then m is equal to ().

A.- 1 B. 0 C. 1 D. 2

9. The price of a pencil in a stationery store is 1.2 yuan, and the price of a ballpoint pen is 2 yuan. Children's Day 1, hold a stationery sale. Pencils are sold at 20% off the original price and ballpoint pens are sold at 10% off the original price. As a result, 60 pieces of two kinds were sold, and the sales amount of * * * was 87 yuan. If X pencils are sold, the equation of one yuan can be listed as () according to the meaning of the question.

a . 1.2×0.8x+2×0.9(60+x)= 87 b. 1.2×0.8x+2×0.9(60﹣x)=87

c . 2×0.9x+ 1.2×0.8(60+x)= 87d 2×0.9x+ 1.2×0.8(60﹣x)=87

10. Given,, the value of is ().

1 1 D. 13

1 1. The following figures are all composed of chess pieces with the same size according to certain rules, in which the first figure has 3 chess pieces, the second figure has 9 chess pieces, the third figure has 18 chess pieces, …, so the number of chess pieces in the first figure is ().

A.84 b . 108 c . 135d . 152

12. Time required for three cars A, B and C to travel between A and B once.

They are 5 hours, 3 hours and 2 hours respectively. Now, for the first time, three cars meet at location A at the same time. Car A leaves first, car B 1 hour later, and car C leaves two hours later. Then, after car C left () hours, the three cars met for the third time at location A.

A.50 B. 5 1 C. 52 D. 53

2. Fill in patiently (this big question is 6 small questions, with 4 points for each small question and 24 points for each small question). Please fill in the correct answer to each question in the table below.

The title is131415161718.

Answer a question.

13. The coefficient of the monomial is.

14. As shown in figure (1), the point is on the line segment, and it is a line segment.

The midpoint of the line segment is.

15 product. Does not contain the quadratic term of x, then the value of m is.

16. At 3: 40 on the clock face, the angle between the hour hand and the minute hand is degrees.

17. Known, and x+y

18. An online shop owner sells two styles of snorkeling equipment. The profit rate of each A is 30%, and the profit rate of each B is 50%. When the number of pieces of style B sold is 40% less than that of style A, the boss gets a total profit margin of 40%. When the number of pieces of style B sold is 80% more than that of style A, the total profit rate obtained by the boss is.

3. When answering questions (this big question ***3 small questions, 19 questions1,20 questions 5,21questions 10, * * 26), each small question must give the necessary calculus process or reasoning steps.

19. Calculation (*** 1 1, where (1) is a minor problem with 5 points and (2) is a minor problem with 6 points).

( 1) ﹣(﹣3)

(2) +(﹣3)2﹣ ×

20. Calculation (5 points)

2 1. Solve the equation (5 points for each question, *** 10)

( 1) (2)

4. When solving the problem (there are 3 small questions in this big question, each small question has a score of 10 and a score of * * 30), each small question must give the necessary calculus process or reasoning steps.

22. Simplify first, then evaluate (10 score)

,

Among them, satisfaction.

2≤t