当你漫步于罗浮宫时，解说员指着一黑色的石柱说：“这是现存世界上最早的比较完备的成文法典。”请你判断，此文物应产生于何处，该法典用哪种文字记载（    ）

阅读理解

    Teenagers are going to have lessons on how to sleep. Materials to teach teenagers how to get enough sleep will be offered to schools across Scotland by the charity Sleep Scotland. The purpose is to help people realize the importance of sleep for young people's physical and emotional health(身心健康)．

    The charity Sleep Scotland said watching TV and using computers and mobile phones at night could stop teenagers from getting the nine hours of sleep they need. It also offers a sleep advising service, saying getting enough sleep can improve grades and physical health. However, less sleep can result in being heavy and a greater risk of feeling worried and hopeless.

    The charity Sleep Scotland hopes to educate young people about why they need a full night's sleep and how to develop good sleeping habits. Most students find it very difficult to get up in the morning and pay attention to their study. Sleep is most surely a problem.

    Research shows that sleep time for teenagers around the world has got down in the past 10 to 20 years. A report by the charity Sleep Scotland said young people often believed they could make up for(弥补) sleep time during the week by sleeping late at weekends. However, by going to bed even later at weekends, they would actually have to experience a change in their body clocks, which would be harmful to their study on Monday mornings.

下列细胞结构中，不是杜鹃鸟和杜鹃花细胞共有的是（　　）

①细胞壁  ②细胞膜    ③线粒体  ④叶绿体  ⑤细胞核．

下列细胞结构中，不是杜鹃鸟和杜鹃花细胞共有的是（　　）

①细胞壁  ②细胞膜    ③线粒体  ④叶绿体  ⑤细胞核．

选择恰当的词义填空。

冷空气把暖空气抬举起来。(  )

新文化运动的内容是（    ）

①提倡民主，反对独裁专制

②提倡科学，反对迷信盲从

③提倡新道德，反对旧道德

④提倡新文学，反对旧文学

如图所示，地面上有一高h的平台，平台下有一倾角可调的挡板，挡板的一端与平台边缘A点的正下方B点重合。将一个可视为质点的小球以v的速度水平推出。适当调节挡板的倾角，小球会刚好垂直撞在挡板上。已知小球下落过程中所受空气阻力忽略不计，当地重力加速度为g。求小球运动的时间是多少？