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问题 选择题
下列方程中，不是一元二次方程的是（　　）
A．
1
2
x2-
2
2
=x		B．7x2=0
C．0.5x2+0.2x=4D．x（1-x2）=2x2
答案

A、B、C都是一元二次方程；

D、是三次方程，故不是一元二次方程．

故选D．

选择题

有关气候与土壤的叙述，正确的是

A．土壤和大气之间不断进行水分和热量的交换，气候直接影响土壤的水热状况及土壤中物理、化学过程的性质与强度

B．在寒冷的气候条件下，土壤中有机质分解较慢，土壤中有机质的含量少

C．在温暖湿润的气候条件下，微生物分解有机质的速度快，土壤中有机质含量丰富

D．气候通过影响岩石的风化过程、地貌形态以及火山活动，直接影响土壤的形成和发育
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填空题

Part 4


Questions 26-45


·Read the following passage and decide which answer best fits each space.
·For questions 26-45, mark one letter A, B, C or D on the Answer Sheet.
Participation (26) high school sports is not a constitutional right. (27) , it is a privilege, paid for by taxpayers, open to students who promise to (28) certain conduct requirements on and off the field. One of these promises is to (29) from using drugs. Drug use is a serious problem among high school students. Studies show that as many as 500, 000 high school students use muscle-pumping, life-destroying substances such as steroids. Many more use illegal drugs, (30) cause discipline problems and (31) the stage for lifelong (32) .
Drug testing works to (33) and identify use. That is why drug testing is required to compete in the Olympics, the National Collegiate Athletic Association and the National Football League. (34) drug testing was instituted by these organizations, use of performance- (35) drugs has been greatly reduced. We should want (36) in schools.
Indeed, many athletes (37) testing programs, and no wonder. Without testing, athletes have to choose between drug use and a competitive disadvantage (38) the field.
Those who challenge the need for drug testing may be forgetting (39) it is like be an adolescent. Peer pressure is enormous, and one of the few effective counter-weights is the fear of being caught. More importantly, once drug use is (40) , a school can (41) to the student before he or she gets addicted or arrested.
For 25 years, public schools (42) by federal judges and civil libertarians, with results everyone can see. It is time (43) decisions on how to run public schools locally (44) officials. There is nothing unconstitutional about asking those who gain the advantages of school-sponsored athletics to contribute to the safety of other players, the integrity of the game and their own well-being. The Supreme Court should leave these programs (45) .

A．if

B．what

C．which

D．when
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