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Escaping from the Earth{{/B}} The Earth has a force that pulls things toward itself. We call this force gravity(地心引力). This is something we live with all the time, and we take it for granted and hardly ever think about it. But it is a most important factor in rocket operation and must be overcome if we are to get anywhere in space, or off the ground at all. Take the throwing of a ball as an example. The harder the ball is thrown, the faster and higher it will go. What is the secret Its speed. If we could throw the ball hard enough it would go up and up forever and never come down. The speed at which it would have to be thrown to do this is known as escape speed. Of course, we cannot throw a ball hard enough beca A. Seventy miles per second. B. Seven thousand miles per hour. C. Twenty-five thousand miles per second. D. Twenty-five thousand miles per hour. [单项选择]《安全生产法》规定，安全生产监督检查人员对检查中发现的安全生产违法行为，( )。
A. 当场予以纠正 B. 责令限期改正 C. 当场予以纠正或者要求限期改正 D. 当场予以查封 [多选题]基本医疗保险包括( )。
A.职工基本医疗保险 B.城镇居民基本医疗保险 C.城乡居民基本医疗保险 D.新型农村合作医疗保险 [简答题]腰阳关(Yāoyángguan，DU3)督脉
[单选题]药材断面显油润表示( )
A. 含淀粉多 B. 含油多 C. 含纤维多 D. 含粘液质多 [判断题]夏季环境温度较高时，要防止液化气管道内留下死角，液体膨胀导致管道内超标。
A.正确 B.错误 [单选题] 题目:.患者在住院期间,亲朋好友前来探望并送来鲜花,
使她满足了哪个层次的需要 A.生理 B.安全 C.爱与归属 D.尊重 E.自我实现 [名词解释]四家诗
[多选题](多选.）设立农村商业银行发起人主要包括。（ ）
A.自然人 B.境内非金融机构、境内银行业金融机构 C.境内非银行金融机构 D.境外银行 [判断题]5S就是大扫除，是形象工程。
A.正确 B.错误 [单选题]下列描述静脉回流量与心输出量的关系,不正确的是:
A. 失血时心输出量减少与静脉回流量有关 B. 每搏输出量在一定程度上取决于静脉回流量 C. 一定范围内静脉回流量增多,心输出量增多 D. 运动时心输出量增多与静脉回流量无关 E. 正常人体静脉回流量与心输出量维持动态平衡 我来回答: 提交
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