Reference answer? First, multiple-choice questions? 1、D2、A3、D4、D5、D6、B7、C8、A9、D 10、C？ Second, fill in the blanks? 1 1、? ≤x & lt； 5 12, ∠EBD=∠C, etc? 13、4.3× 10-5? 14、? 15、36 16、 1∶2? 17、4? 18,6 Third, answer the question? 19、( 1)- 1? (2) ellipsis? 20 copies, 20 copies? 2 1, (1) Omit (2) Diamond? 22. The average value of (1) is 10, the same? (2) What is the difference between Party A? What's the difference between Party B? , indicating that the sales of refrigerator B are stable? (3) The price of a refrigerator is increasing, so we should use it more. ? 23 、( 1)0.3m(2) 18？ 24. (1) omit (2)25, (1) equilateral triangle (2)△CBQ? △CPB？ (3) 10? 26.( 1) Which is better for raising soft-shelled turtles in pond X? The solution is 6≤x≤8? Since x is an integer, then x = 6,7,8? ∴ There are three arrangements: 6 ponds for soft-shelled turtle and 4 ponds for eel; Use 7 ponds to raise turtles and 3 ponds to raise Monopterus albus; Use 8 ponds to raise soft-shelled turtle and 2 ponds to raise eel. ? (2) income = 0.3 >; 0, so? At that time, the income was the biggest, that is, turtles were raised in 8 ponds and eel was raised in 2 ponds, and the income was the biggest. ? (3) When the income m=0.3, no more than 8 fish ponds will be arranged at will; ? When m> is 0.3, the total benefit of raising Monopterus albus is the largest; ? When m< is 0.3, turtle is raised in 8 ponds and eel is raised in 2 ponds, which makes the most profit. ? 27、( 1)=? ; (2)45 (3)45 ? 28 、( 1)B(？ ,0)? (2)①? Seconds ② at 0 o'clock