257×62的积是四位数。
词汇运用 I have a good____ (男孩) friend。____ (他的) name is Tony. He likes____ (英语). He ____ (有) a nice room. You can see two____ (椅子) and a ____ (电脑) in it. He likes____ (运动). He likes playing ____ (篮球). He likes apples and ____ (草莓). So he is____ (健康的).
某溶液中可能含有SiO32﹣、OH﹣、CO32﹣、SO42﹣、AlO2﹣、HCO3﹣、Na+、Mg2+、Fe3+、Al3+等离子.当向该溶液中逐滴加入一定物质的量浓度的盐酸溶液时,发现生成沉淀的物质的量随盐酸溶液的体积变化如图所示.下列说法正确的是( )
“紫荆开后白莲开,喜事翩跹接踵来。神州大地齐欢庆,一国两制谱新篇。”这首诗歌中的“喜事”是指( )