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Space is a dangerous place, not only because of meteors (流星) but also because of rays from the sun and other stars. The atmosphere again acts (67) our protective blanket on (68) . Light gets through, and this is essen- tial (69) plants to make the food which we (70) . Heat, (71) , makes our environments tolerable and some ultraviolet rays (紫外线 ) penetrate the (72) . Cosmic ( 宇宙的) rays of various kinds come (73) the air from outer space, but (74) quantities of radiation from the sun are screened off. As (75) as men leave the atmosphere they are (76) to this radiation; (77) their spacesuits or the walls of their spacecraft, if they are inside, (78) prevent a lot of radiation damage. Radiation is the greatest known danger to explorers in (79) . Doses of radiation are measured in (80) called "reins (霍姆)". We all 81 radiation here on earth from the sun, from cosmic rays and from radioactive minerals. The " (82) " dose of radiation that we receive each year is about 100 millirems; it (83) according to where you live, and this is a very rough estimate. Scientists have reason to think (84) a man can (85) up with far more radia- tion (86) this without being damaged; the figure of 60 rems has been agreed.
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对于一个健康的、正在成长的公司来说，经营活动现金净流量应当是正数，投资活动现金净流量是正数，筹资活动现金净流量正、负数相间。( )
“实现社会和谐，建设荚好社会，始终是人类孜孜以求的一个社会理想，也是包括中国共产党在内的马克思主义政党不懈追求一个社会理想。根据马克思主义基本原理和我国社会主义建设的实践经验，根据新世纪新阶段我国经济发展的新要求和我国社会出现的新趋势，新特点，我们所要建设的社会主义和谐社会，应该是民主法治、公平正义、诚信友爱、充满活力、安定有序、人与自然和谐相处的社会。” 根据材料请回答： (1)上述材料体现了马克思主义哲学的什么原理阐述这一原理的基本内容。 (2)运用矛盾同一性原理分析说明构建社会主义和谐社会的重要性。
同一图样只能选用同一比例。( )
Those baby-faced people now have another reason to be smug (自鸣得意的 ): a new Danish study says looking young (47) means a longer life. Research suggests that people who look younger than their years also live longer. In 2001, Danish researchers (48) physical and cognitive tests on more than 1,800 pairs of twins over aged 70, as well as taking photos of their faces. Three groups of people who didn’t know the twins’ real ages guessed how old they were. The researchers then (49) how long the twins (50) over 7 years. The experts found that people who looked younger than their (51) age were far more likely to survive, even after they (52) for other factors like gender and environment. The bigger the difference in (53) age within any twin pair, the more likely it was that the older-looking twin died first. They also found a possible biological (54) : people who looked younger also tended to have longer telomeres (端粒), a key DNA (55) that is linked to aging. People with shorter telomeres are thought to age faster. In the Danish study, the more fresh-faced people had longer telomeres. The authors said that perceived age, which is widely used by doctors as a general (56) of a patient’s health, is a good biomarker of aging that predicts survival among people over age 70.[A] actual[I] component[B] predictor[J] apparently[C] perceived [K] substance[D] explanation [L] survived[E] adjusted [M] indicator[F] mentally [N] active[G] tracked [O] conducted[H] adopted
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