题目内容
调查某草原田鼠数量时，在设置1公顷的调查区内放置100个捕鼠笼，一夜间捕获鼠32头，将捕获的鼠经标记后在原地释放。数日后，在同一地方再放置同样数量的捕鼠笼，这次共捕获30头，其中有上次标记过的个体10头。若该地区田鼠种群个体总数为N，N=( )头。
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TEXT AAt the age of 16, Lee Hyuk Joon’s life is a living hell. The South Korean 10th grader gets up at 6 in the morning to go to school, and studies most of the day until returning home at 6 p. m. After dinner, it’s time to hit the books again—at one of Seoul’s many so-called cram schools. Lee gets back home at 1 in the morning, sleeps less than five hours, then repeats the routine—five days a week. It’s a grueling schedule, but Lee worries that it may not be good enough to get him into a top university. Some of his classmates study even harder.South Korea’s education system has long been highly competitive. But for Lee and the other 700,000 high-school sophomores in the country, high-school studies have gotten even more intense. That’s because South Korea has conceived a new college-entrance system, which will be implemented in 2008. This year’s 10th graders will be the first group evaluated by the new admissions standard, which places more emphasis on grades in the three years of high school and less on nationwide SAT-style and other selection tests, which have traditionally determined which students go to the elite colleges.The change was made mostly to reduce what the government says is a growing education gap in the country: wealthy students go to the best colleges and get the best jobs, keeping the children of poorer families on the social margins. The aim is to reduce the importance of costly tutors and cram schools, partly to help students enjoy a more normal high-school life. But the new system has had the opposite effect. Before, students didn’t worry too much about their grade-point averages; the big challenge was beating the standardized tests as high-school seniors. Now students are competing against one another over a three-year period, and every midterm and final test is crucial. Fretful parents are relying even more heavily on tutors and cram schools to help their children succeed.Parents and kids have sent thousands of angry online letters to the Education Ministry complaining that the new admissions standard is setting students against each other. "One can succeed only when others fail," as one parent said.Education experts say that South Korea’s public secondary-school system is foundering, while private education is thriving. According to critics, the country’s high schools are almost uniformly mediocre—the result of an egalitarian government education policy. With the number of elite schools strictly controlled by the government, even the brightest students typically have to settle for ordinary schools in their neighbourhoods, where the curriculum is centred on average students. To make up for the mediocrity, zealous parents send their kids to the expensive cram schools.Students in affluent southern Seoul neighbourhoods complain that the new system will hurt them the most. Nearly all Korean high schools will be weighted equally in the college-entrance process, and relatively weak students in provincial schools, who may not score well on standardized tests, often compile good grade-point averages.Some universities, particularly prestigious ones, openly complain that they cannot select the best students under the new system because it eliminates differences among high schools. They’ve asked for more discretion in picking students by giving more weight to such screening tools as essay writing or interviews.President Roh Moo Hyun doesn’t like how some colleges are trying to circumvent the new system. He recently criticized "greedy" universities that focus more on finding the best students than trying to "nurture good students". But amid the crossfire between the government and universities, the country’s 10th graders are feeling the stress. On online protest sites, some are calling themselves a "cursed generation" and "mice in a lab experiment". It all seems a touch melodramatic, but that’s the South Korean school system. According to the passage, there seems to be disagreement over the adoption of the new system between the following groups EXCEPT（）
小麦植株最上一片叶称为旗叶，它对小麦籽粒的产量起着决定性的作用。与这种功能关系最密切的结构特点是下面哪些( ) ①细胞排列紧密 ②细胞中叶绿体数目较多 ③细胞中线粒体较多 ④叶绿体中基粒内类囊体数目多 ⑤细胞中具有中心体
已知某植物的基因型是AaBbCc，三对基因分别位于三对同源染色体上。若对该植物进行花药离体培养，然后恢复其可育性，共得到N个植株，则其中aaBBcc的数目是( )
TEXT AAt the age of 16, Lee Hyuk Joon’s life is a living hell. The South Korean 10th grader gets up at 6 in the morning to go to school, and studies most of the day until returning home at 6 p. m. After dinner, it’s time to hit the books again—at one of Seoul’s many so-called cram schools. Lee gets back home at 1 in the morning, sleeps less than five hours, then repeats the routine—five days a week. It’s a grueling schedule, but Lee worries that it may not be good enough to get him into a top university. Some of his classmates study even harder.South Korea’s education system has long been highly competitive. But for Lee and the other 700,000 high-school sophomores in the country, high-school studies have gotten even more intense. That’s because South Korea has conceived a new college-entrance system, which will be implemented in 2008. This year’s 10th graders will be the first group evaluated by the new admissions standard, which places more emphasis on grades in the three years of high school and less on nationwide SAT-style and other selection tests, which have traditionally determined which students go to the elite colleges.The change was made mostly to reduce what the government says is a growing education gap in the country: wealthy students go to the best colleges and get the best jobs, keeping the children of poorer families on the social margins. The aim is to reduce the importance of costly tutors and cram schools, partly to help students enjoy a more normal high-school life. But the new system has had the opposite effect. Before, students didn’t worry too much about their grade-point averages; the big challenge was beating the standardized tests as high-school seniors. Now students are competing against one another over a three-year period, and every midterm and final test is crucial. Fretful parents are relying even more heavily on tutors and cram schools to help their children succeed.Parents and kids have sent thousands of angry online letters to the Education Ministry complaining that the new admissions standard is setting students against each other. "One can succeed only when others fail," as one parent said.Education experts say that South Korea’s public secondary-school system is foundering, while private education is thriving. According to critics, the country’s high schools are almost uniformly mediocre—the result of an egalitarian government education policy. With the number of elite schools strictly controlled by the government, even the brightest students typically have to settle for ordinary schools in their neighbourhoods, where the curriculum is centred on average students. To make up for the mediocrity, zealous parents send their kids to the expensive cram schools.Students in affluent southern Seoul neighbourhoods complain that the new system will hurt them the most. Nearly all Korean high schools will be weighted equally in the college-entrance process, and relatively weak students in provincial schools, who may not score well on standardized tests, often compile good grade-point averages.Some universities, particularly prestigious ones, openly complain that they cannot select the best students under the new system because it eliminates differences among high schools. They’ve asked for more discretion in picking students by giving more weight to such screening tools as essay writing or interviews.President Roh Moo Hyun doesn’t like how some colleges are trying to circumvent the new system. He recently criticized "greedy" universities that focus more on finding the best students than trying to "nurture good students". But amid the crossfire between the government and universities, the country’s 10th graders are feeling the stress. On online protest sites, some are calling themselves a "cursed generation" and "mice in a lab experiment". It all seems a touch melodramatic, but that’s the South Korean school system. According to critics, the popularity of private education is mainly the result of（）
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