Grade 7 (Grade 2) Mathematics Mid-term Review Test \x0d\ 1. Choose carefully (there is only one correct answer for each small question, with 3 points for each question and 30 points for * * *) \ x0d \ 1. The correct statement is (). \x0d\( 1) is the antipodal angle; (2) There is one and only one straight line parallel to the known straight line; (3) Two straight lines perpendicular to the same straight line are parallel to each other; (4) Two straight lines are cut by the third straight line, and the same angle is equal; (A)0 (B) 1 (C)2 (D)3 \ x0d \ 2。 If a river turns into the bay twice and its flow direction remains the same, then the angle of turning into the bay twice may be () \x0d\(A) the first turn right is 50 degrees, and the second turn left is 10. \x0d\(B) Turn left 50 degrees for the first time and turn left 130 degrees for the second time; \x0d\(C) Turn right 50 degrees for the first time and 50 degrees for the second time; \x0d\(D) Turn left 50 degrees for the first time and turn right 50 degrees for the second time \ x0d \ 3. As shown in the right figure, the condition that AB‖CD cannot be judged is () \ x0d \ (a) ∠ B+∠ BCD =1800; (B)≈ 1 =∠2； (C)∠3 =∠4； (D)∠B=∠5。 \x0d\4。 It is known that ∠A and ∠B are complementary, while ∠ B and ∠C are complementary. If ∠ A = 50, the degree of ∠C is (). 6. It is completely flat, so the value of k is () \x0d\(A)6(B)(C)-6(D)\x0d\7. The probability that a puppy walks around on the square brick as shown in the figure and finally stops on the shadow square brick is () \x0d\(A) (b). \x0d\(B) Approximation 3. 197 is accurate to one thousandth, with four significant figures. \x0d\(C) The approximate value of 5,000 and the approximate value of 5,000 have the same accuracy. \x0d\(D) The significant figures of divisor 23.0 and divisor 23 are both 2 and 3. \ x0d \ x0d \ 9。 As shown in the figure, ∠ 2+∠ 3 = 180, ∠ 2 = 70 and ∠ 4 = 80, then ∠1= () ∠ and ∠ EMD = 65, \ x0d. As shown in the figure. Fold a rectangular strip of paper with the same width, if ∠ 1=620, ∠ 2 = _ _ _ _ _ degrees \ x0d \ x0d \ 14. As shown in the figure, AB⊥AC and AD⊥AE are all in the figure. Use black and white hexagonal floor tiles to make several patterns according to the following rules, so the white floor tile with the nth pattern has _ _ _ _ _ _ _ _. \x0d\\x0d\ III。 Seriously (***55 points) \ x0d \ 16. (5 points) 10000 lottery tickets, the grand prize 1 one, the first prize 10, and the second prize 100. If a person's shopping just exceeds 100 yuan, what is the probability of winning the first prize, the first prize, the second prize and the prize? \x0d\\x0d\ 17。 (5 points) \ x0d \ x0d \18. (6 points) Given x=, y=- 1, the water will boil when the temperature reaches 100C under the standard atmospheric pressure. (2) Without water, seeds germinate; (3) Randomly select five people from a class, all of whom are boys. (4) It will rain in this city tomorrow; (5) Turn on the TV, a news broadcast is being broadcast; (6) The reciprocal of a positive number is itself \x0d\ A: The uncertain event is: the inevitable event is: \ x0d \ x0d \ the impossible event is: \ x0d \ x0d \ 20. As shown in the figure, a‖b, b‖c, write the relationship between the angles in the figure. (Only write the conclusion, and get 1 point for the correct one, with a maximum of 8 points) \ x0d \ x0d \ 2 1. (8 points) As shown in the figure, ∠ l = ∠l=∠2, DE⊥BC, AB⊥BC, then ∠ A. Explain the reason. (Please indicate the basis of each step of reasoning) \x0d\ Conclusion: ∠A is equal to ∠3, for the following reasons: \x0d\\x0d\∵DE⊥BC, AB⊥BC (known) \ x0d \ ∠ 2 = \x0d\( 1) Xiaoming thinks it is equally possible to draw a ball from it, either a white ball or a red ball. Do you agree with him? Why? \x0d\(2) After mixing evenly, find a ball from it and find the probability that it is not a white ball; \x0d\(3) After mixing evenly, you can randomly find a ball from it. If the probability of finding the red ball is zero, how to add the red ball?