As shown in the figure, in diamond ABCD, e and F are the points on BC and CD respectively, ∠ B = ∠ EAF = 60 ° and ∠ BAE = 20 ° to find the degree of ∠ CEF

Connecting AC, as shown in the figure, connecting AC, connecting AC, connecting AC, as shown in the figure, connecting AC, in the diamond ABCD, in the diamond ABCD, ab = BC, ab = BC, \ \\\\\? In the diamond ABCD, ab = BC, \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\sidethree According to the properties of the external angle of the triangle, ∠ AEF + ∠ CEF = ∠ B + ∠ BAE,  60 ° + ∠ CEF = 60 ° + 20 °, the solution ∠ CEF = 20 ° is obtained

RELATED INFORMATIONS

1. In the past, it took 8 hours for Letong toy factory to produce 1200 dolls. After the technological innovation, it took only 6 hours to complete the production. What percentage of the working time has been shortened? How much has the work efficiency been improved? (one decimal place before the percent sign)
2. -Two thirds power of 1
3. -How to calculate the opposite number of 1 / 2 square
4. How to calculate the square of a (2-1)
5. When a = 1 / 2, B = 2, how to find the value of the algebraic formula
6. If a minus B equals 1, then the square of 2A minus 4AB plus the square of 2B plus 2005 is
7. Simple calculation of 8 / 9 + (1 / 4 minus 1 / 9) + 3 / 4
8. 3 / 4 x 8 / 9 + 3 / 4 divided by 9
9. 8 / 9 * [3 / 4 - (10 / 19-1 / 4)] is easy to operate and can be calculated by disjunction
10. How to calculate 1.38 times 1.2 times 0.5
11. How to judge whether a function is decreasing or increasing, odd or even, especially logarithmic function
12. The area of the quadrilateral is calculated by the coordinates a (3, - 2) B (6, - 2) C (7,5) d (- 1,3) of each vertex of the quadrilateral ABCD in the coordinate system
13. emergency 2、 Structure of eukaryotic cells 5. Cell wall:_________ There is a cell wall outside the cell, and the main chemical composition is_________ Its function is to support and protect. Its nature is transparent (prokaryotes also have cell walls, the main components of which are 6. The main components of cell membrane are as follows_________ 、___________ 、_________ 7. The structure of cell membrane was as follows_________ It is the basic scaffold of cell membrane_________ ；________ It combines with bilayer phospholipid molecules in three ways: covering, penetrating and inlaying_________ It is related to cell recognition, with glycoprotein side indicating that it is cellular_________ . 8. The structure and function of cell membrane are as follows_____________ For example, pseudopodia can extend from any part of amoeba, and some human leukocytes can phagocytize bacteria. The completion of these physiological functions depends on the fluidity of cell membrane 10. The cytoplasm mainly consists of__ And__ . 11. The organelles involved in the synthesis, transportation and secretion of secretory proteins such as insulin are as follows_ In the process of insulin synthesis, the place of synthesis is________ ¬¬¬¬¬____ Insulin is transported through___________ To do this, insulin needs to be processed before it is secreted___________ In the process of synthesis and secretion___________ Provide energy 11. In eukaryotic cells, the organelles with bilayer membrane structure are:________ ¬¬¬¬¬__ 、__________ ¬¬¬¬¬____ The organelles with monolayer structure are as follows________ ¬¬¬¬¬____ 、________ ¬¬¬¬¬____ 、____________ &What is not membrane structure_______ 、_ ¬¬¬________ ¬¬¬¬¬____ In addition, the nuclear membrane of the nucleus is________ &Cell membrane is a kind of membrane____________ But they are not organelles 12. Differences between animal and plant cells: plant cells have____________ And____________ However, animal cells did not, and mature plant cells had obvious differentiation____________ But not in animal cells; in lower plant and animal cells____________ In addition, higher plant cells do not____________ It plays different roles in animal and plant cells 14. The nucleus exists in most eukaryotic cells; there is no real nucleus in prokaryotic cells; and there is no nucleus in some eukaryotic cells____________ . 15. Nuclear structure: a____________ Control the flow of substances into and out of the nucleus, and____________ The membrane is connected to facilitate the transport of materials____________ It is the channel for macromolecular substances to enter and leave the nucleus and the incoherent part on the nuclear membrane; c、____________ In cell cycle____________ The period disappeared____________ The period of time appeared d、____________ It is a dark colored substance in the nucleus which is easy to be dyed by alkaline dyes____________ And___________ Composition. Yes____________ Two substances in____________ There are two different forms of cells in the period! (3) Nuclear function: Yes____________ It is the place of storage and replication; it is the control center of cell genetic characteristics and metabolic activities 1. The chemical essence of most enzymes is (the site of synthetase is mainly hydrolase), and some are 2. The characteristics of enzyme: under certain conditions, it can make the complex chemical reaction in organism quickly, and the sum of enzyme before and after reaction does not change 3. The characteristics of enzyme: ①: the catalytic efficiency is much higher than that of inorganic catalyst. ②: each enzyme can only catalyze chemical reactions of compounds. ③ the enzyme needs appropriate and other conditions: too acid, too alkali and high temperature, which can destroy the enzyme and make it active 4. Enzymes are produced by living cells and work both inside and outside the cells. For example, digestive enzymes work in the digestive tract. Most enzymes are controlled by their synthesis, so the decisive factor of enzymes is 5. It is necessary to remove the cell wall without damaging the internal structure of the cell. The correct idea is that the main component of the cell wall is specific, and the removal of the cell wall should be selected to decompose it
14. The intersection of diagonal AC and BD of trapezoid ABCD and point O, it is known that the top and bottom of trapezoid is 2, and the area of triangle ABO is equal to 2 / 3 of the area of triangle BOC, so the triangle can be obtained Ratio of AOD to BOC area of triangle (Butterfly Theorem) 2 as shown in the figure, in rectangular ABCD, ab = 6, ad = 2, AE = EF = fr, calculate the shadow area one two
15. I can't remember which side is a stone, which is composed of five squares (one in the upper left and one in the middle left, one in the middle right and one in the lower right) cut two times to make a square
16. The original price of a piece of clothing is 300 yuan. The price will be increased by 10% in August, but it will be reduced by 10% in September. What's the current price? Dear brothers and sisters, please teach me the kind-hearted trouble, OK? I'm very grateful here~~
17. 1. Put the following numbers in the circle of the number set where it is located: - 18,22 / 7,3.1416,02004,3 / 5,0.142857,95%, 200%, π Set of positive numbers: Set of integers: Negative score set: 2. Regular questions - 1,1 / 2, - 1 / 3,1 / 4, - 1 / 5,1 / 6 ① Fill in 7.8.9 ② The number 2004 is (). If the number in this column is arranged infinitely, it will be closer to () 3. Let a ＞ 0, B ＜ 0, and | a ＜ B |, connect a, - A, B, - B with ＜ sign is () Please help me
18. If a, B are opposite numbers, C, D are reciprocal numbers, and X is equal to the square of - 4, then the value of (cd-a-b) X-2 / 1 x is?
19. The original price of a washing machine is 1450 yuan. Now it is sold at a 20% discount, but the price is still higher than the cost. 19. How much is the cost of this washing machine?
20. 1. The rules of points in football match: in order to win one game, get 3 points, draw one game, lose one game, get 0 points. A football team needs to play 14 games in a certain season, now it has played 8 games, lost one game, get 17 points (1) How many games did this team win in the first eight games? (2) How many points can a player score in 14 games? (3) Through the analysis of the game situation, this team has played 14 games. If the score is not less than 29 points, it can achieve the expected goal. Please analyze how many games this team has to win in the next six games to achieve the expected goal? 2. The distance between station a and station B is 450km; a slow train from station a runs 65km per hour; an express train from station B runs 85km per hour (1) How many hours will the two cars meet each other? (2) The express train will drive for 30 minutes first, and the two trains will face each other. How many kilometers will the slow train run? How many kilometers will the two trains meet? The express train will drive for 30 minutes first, and the two trains will face each other. How many hours will the slow train run?