U.S. Scientists Confirm Water on
Mars NASA scientists said that Mars was covered once by vast lakes, flowing rivers and a variety of other wet environments that had the potential to support life. Laboratory tests aboard NASA’s Phoenix Mars Lander have identified water in a soil sample. The lander’s robotic arm delivered the sample Wednesday to an instrument that identifies vapors produced by the heating of samples. "We have water," said William Boynton of the University of Arizona, lead scientist for the Thermal and Evolved-Gas Analyzer, or TEGA. "This is the first time Martian water has been touched and tasted. " The robotic arm is a critical part of the Phoenix Mars mission. It is needed to trench into the icy layers of northern polar Mars and deliver samples to instrum A. Vast lakes. B. Flowing rivers. C. Water in a soil sample. D. Living things. [单选题]液化石油气无色、无臭、( )。
A.无毒 B.中毒 C.剧毒 D.微毒 [单项选择]某城区A地块因旧城改造拟进行拆迁,房屋拆迁管理部门书面通知有关部门暂停为拆迁范围内的单位和个人办理房屋新建、改建、出租等审批手续(由于一些突然的原因)。
拆迁人应当在房屋拆迁( )确定的拆迁范围和拆迁期限内,实施房屋拆迁。 A. 施工方案 B. 计划 C. 目标 D. 许可证 [单项选择]下列任务中,相传曾整理《诗》《书》等古代典籍,并删修《春秋》的是()
A. 孔子 B. 老子 C. 孟子 D. 荀子 [单项选择]重量增加时,平飞最小速度(),有利速度(),平飞最大速度()。
A. 增大,增大,增大 B. 减小,减小,减小 C. 增大,减小,减小 D. 增大,增大,减小 [单选题]37.人工喂养儿体重为7kg,每天能量需要量正确的是
A..每天给总热量2926kJ(700kcal) B..每天给总热量770kcal C..每天给5%糖牛乳770ml D..每天加1个鸡蛋 E..每天加肉末少许 [判断题]《安规》条文说明第2.1.12条,成段更换轨枕、成段破底清筛是指连续3根轨枕及以上。
A.正确 B.错误 [单选题]高处(离地2米及以上)作业,严禁在()行走。
A.地面上 B.车帮上 C.主梁上 D.货件上 我来回答: 提交
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