Passage Three
According to the best historical and archaeological evidence, it is estimated that it took about 800 thousand to 1 million years for the earth's population to reach the 250 total which existed at the end of the first century 'after Christ. For some time after that, disease, famine, and war kept the population increase down to a fraction of 1 percent a year so that more than 15 centuries passed before the population reached 500 million. But in the next 250 years, up to 1850, the population of the world shot up to the 1 billion mark, and today it has reached 3 billion. It is predicted by United Nations investigators that in the next 35 years the population of the world will double. When experts are asked what the most effective measure which overpopulation poses, they reply that at least three measur A. estimates based on current population growth B. references in literature and mythology C. estimates based on previous population growth D. written records and cultural remains [简答题] key to success:C mechanism
[单项选择]Miller窥盘主要用于( )
A. 观察动力 B. 嗜酸性粒细胞计数 C. 疟原虫检查 D. 网织红细胞计数 E. 嗜碱性粒细胞计数 我来回答: 提交
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