教科版小学六年级科学期末重点复习题及答案

Word文档下载后可自行编辑1/1教科版小学六年级科学期末重点复习题及答案color=font-weight:bold;font-weight:bold;font-weight:bold;color=font-weight:bold;color=font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;color=font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;font-weight:bold;style=color=font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration:underline;font-weight:bold;text-decoration: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减少垃圾）很重要，常用的方法是（减少丢弃）和（重新使用）。＜/span＞＜br＞＜br＞＜span＞7、＜/span＞＜span＞日常生活中以下垃圾是可以减少的：（1）双面打印可以节约纸张（2）自带喝水杯外出，少买瓶装饮料（3）尽量少用或不用一次性用品，以减少纸和塑料的丢弃……＜/span＞＜br＞＜br＞＜span＞8、（过度包装）会造成（资源浪费）而且产生大量垃圾。＜/span＞＜br＞＜br＞＜span＞9、垃圾中的一些原材料可以重新（回收利用），包括纸、金属、塑料、玻璃等。＜/span＞＜span＞这样可以（减少垃圾、节约资源）。＜/span＞＜br＞＜br＞＜span＞10、要有效地回收垃圾，必须改变（垃圾混装）的习惯，对生活垃圾进行（分类）和（分装）。＜/span＞＜br＞＜br＞＜span＞11、垃圾分类、分装便于垃圾（回收利用）和对一些（有毒垃圾）的处理。＜/span＞＜br＞＜br＞＜span＞12、对自然环境威胁最大的五种物质，电池里就包含了三种：（汞）、（铅）、（镉）。＜/span＞＜br＞＜br＞＜span＞13、（堆肥法）可以有效减少垃圾并形成（肥料）。＜/span＞＜br＞＜br＞＜span＞14、减少固体垃圾的科学方法是（减少丢弃）、（重新使用）和（回收利用）。＜/span＞＜br＞＜br＞＜span＞15、人们生活中要用掉大量的水，（淡水资源）很紧缺。＜/span＞＜br＞＜br＞＜span＞16、由于（人口迅速增长）、（环境污染）和（全球气候变暖），目前60%的大陆面临淡水资源不足，100多个国家严重缺水，其中最严重的国家达（40多个）。＜/sp