题干

取甲、乙两个瓶子,甲瓶中装有萌发的种子,乙瓶中装有等量的煮熟的种子?两瓶分别用橡皮塞塞严,放在温暖的地方。一天后把燃烧的蜡烛分别放入两瓶内,观察到(  )

A:甲瓶火焰熄灭,乙瓶不熄灭

B:甲、乙两瓶火焰都熄灭

C:甲瓶火焰不熄灭,乙瓶熄灭

D:甲、乙两瓶火焰都不熄灭

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答案(点此获取答案解析)

A

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    Hello,everybody.Welcome to surf on a new Web site—SCIENCE NEWS FOR KIDS!

    Our goal is to offer timely items of interest to kids,accompanied by suggestions for hands on activities,books, articles,Web resources,and other useful materials.

    Our emphasis is on making the Web site attractive by offering kids opportunities to comment on and grade the subject matter,get ideas for science projects,and try out math puzzles.At the same time,we offer teachers creative ways of using science news in their classrooms.

    The Science News for Kids Web site,supported by several corporations and foundations,strengthens the usefulness of Science News in the middle-school classroom and offers entertaining reading and activities for students interested in science.

    A section of the Science News for Kids Web site is devoted to particular interests.At present,we have six such zones: a weekly brainteaser(难题)for those who enjoy solving and inventing puzzles (PuzzleZone),entertaining science-fiction composition exercises for those interested in writing (SciFiZone),and weekly science short description along with science project ideas and tips (ScienceFairZone).The GameZone contains a small selection of logic and memory games.The TeacherZone has materials,including question sheets related to the feature article of the week,so that teachers can bring science news topics to the classroom.The LabZone features a weekly hands on activity or science project idea.In the future,we might add additional zones,for example,for kids interested in robotics,the environment,computers,math,or veterinary(兽医的)medicine and animals.

    Contact us at editor@snkids.com.         Science News for Kids            1719 N Street,N.W.

    Washington,DC 20036                 Phone :202-785-2255             Fax: 202-659-0365

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五年规划是中国国民经济计划的重要部分,为国民经济发展远景规定目标和方向,是中国经济社会发展的行动纲领,将引领中国未来五年的发展布局。

材料一:党的十八届五中全会通过了《中共中央关于制定国民经济和社会发展第十三个五年规划的建议》。该建议提出,要实现“十三五”时期发展目标,破解发展难题,厚植发展优势,必须牢固树立并切实贯彻创新、协调、绿色、开放、共享的发展理念。这五大发展理念将引领我国“十三五”乃至更长时期的经济社会发展。

材料二:2015年12月2日,中国社会科学院发布了《人口与劳动绿皮书:中国人口与劳动问题报告No.1酵。《报告》显示,“十三五”时期,经济结构和产业结构调整进入关键期,就业结构调整面临更大的不确定性,结构性失业风险将会明显增大。一方面,中国经济将逐渐转变成为服务业主导的经济形态,依靠土地、房地产、基础设施等大规模投资的增长模式将失去动力,依靠廉价劳动力、资源等的粗放型产业将加快淘汰,经济结构和产业结构的变化也将带来就业结构的转变。在这个过程中,部分劳动力将因不适应而被淘汰。另一方面,目前劳动力市场上普通工人工资迅速上涨,助推了教育的机会成本,导致不少青年过早进入劳动力市场,人力资本水平低,对劳动力市场的长期适应能力不强。