某同学设计了一个用电磁打点计时器验证动量守恒定律的实验：在小车A的前端粘有橡皮泥，推动小车A使之做匀速运动，然后与原来静止在前方的小车B相碰并粘合成一体，继续做匀速运动．他设计的装置如图（a）所示．在小车A后连着纸带，电磁打点计时器所用电源频率为50Hz，长木板下垫着小木片以平衡摩擦力．

当人所处的环境温度从25℃降至5℃时，耗氧量、尿量、抗利尿激素及体内酶活性的变化依次为：（  ）

影响日本樱花开放时间自南向北推迟的主要因素是（　　）

 某初中化学社团﹣﹣“拉瓦锡实验室”的活动丰富多彩．下面是他们以“化学与社会发展”为主题的两次活动记录：

活动1：在观看了“西气东输”与“石油分馏”等视频后．通过小组讨论，同学们认识到：

①____、石油、天然气是人类社会重要的自然资源．天然气的主要成分是甲烷，甲烷完全燃烧的化学方程式是　____ ．

②现在化石燃料等不可再生能源面临枯竭，化石燃料对环境的影响也不容忽视．所以，开发和利用风能、____等新能源成为越来越迫切的要求．

③人们将化石燃料通过化学工艺可以制造和合成价值更高的药物、化学纤维、塑料和合成橡胶等．其中，塑料属于____材料．随意丢弃会造成“白色污染”．

活动2：同学们展示了各自收集到的关于“化学物质与健康”的相关资料及一些常见食品，如：高钙牛奶、加碘食盐等．并针对“化学制品对人体有益还是有害”展开了激烈的辩论，从而认识到钙、铁、锌等元素对人体健康有重要作用，如缺铁元素会引起缺铁性贫血，缺钙元素会引起____；还认识到一氧化碳、甲醛等物质对人体健康的危害．通过这样的社团活动，大家形成了“保护自然，关爱生命”的共识．

阅读下文，完成小题。

江南雨

汪国真

                                                                                                     江南也多晴日

                                                                                                     但烙在心头的

                                                                                                     却是江南的

                                                                                                     蒙蒙烟雨

                                                                                                     江南雨斜斜

                                                                                                     江南雨细细

                                                                                                     江南雨斜

                                                                                                     斜成檐前翩飞的燕子

                                                                                                     江南雨细

                                                                                                     细成荷塘浅笑的涟漪

                                                                                                     江南雨

                                                                                                     是阿婆河边捣的衣

                                                                                                     江南雨

                                                                                                     是阿妈屋前舂的米

                                                                                                     江南雨

                                                                                                     是水乡月上柳梢的洞箫

                                                                                                     江南雨

                                                                                                     是稻田夕阳晚照的竹笛

                                                                                                     江南雨中

                                                                                                     有一把圆圆的纸伞

                                                                                                     江南雨外

                                                                                                     有一个圆圆的思绪

                                                                                                     江南雨有情

                                                                                                     绵绵的使江南人不想离别

                                                                                                     江南雨有意

                                                                                                     密密的使乡外人不愿归