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.一杯80克的盐水中,有盐4克,现在要使这杯盐水中盐与水的比变为1∶9,需加多少克盐或蒸发多少克水? 一杯80克的盐水,有盐4克,现在要使这杯盐水中盐与水的比变为1：9,需加多少克盐 80克盐水中有盐20克,盐与水的比是多少?如果在加入5克盐,这时盐与水的比是多少? 武汉长江大桥和南京长江大桥的修建背景武汉长江大桥 还是 南京长江大桥修建时间,是我国自己设计规划吗? 一杯盐水重80克,盐和水的比是1；4,再往杯中加入多少水,才能使盐与水的质量比是2:15 某食堂去年计划烧煤180吨,实际只烧了135吨,实际比计划节约了百分之几? 南京长江大桥全长多长? 南京长江大桥的长度是多少 南京长江大桥有多长有多长 有一种含盐20%的盐水60千克,要加入多少千克含盐50%的盐水,才能配制成含盐25%的用小学生的方法解 有一种含盐20%的盐水60千克,要加入多少千克含盐50%的盐水,才能配制成含盐25%的盐水最好不用方程 《all good things》的歌词谁知道啊,谢谢 ! 英语翻译who love my downfalland it's just too coldyou show me true friendbaby i was so soyou might as well call me up physically you know,you got me only into extremesand i can't believe itand don't know what to thinksometime around it was so lov but he was full of ideas of which few people saw the value翻译 翻译：The city is full of people we can't reach the room is full of people.这里be full of 为什么要用is很多人不是应该用are吗?如题、the room is full of people,这里be full of 为什么要用is很多人不是应该用are吗?还是people是不可数的? the suppermarket is always full of people改为同义句 the supermarket ( ) always ( ) 求Lifehouse的Good Enough的歌词和中文翻译,谢,急... 求：这首歌的英文歌词“Lost Good Things (童话破灭)” 物体静止在水平面上当用f1=5N的水平拉力拉物体时物体加速度为a1=1m/s当用f2=8N的水平拉力拉物体时加速度为 用2N的水平拉力拉一放在水平地面上的物体,可使它获得1m/s^2的加速度；用3N的水平拉力拉此物体,可使它获得2m/s^2的加速度.那么用4N的水平拉力拉此物体,沿原水平地面运动时,物体的加速度为__ 在公交车上是on the bus还是in the bus “在公交车上”是on the bus还是in the bus?RT on the bus 和in the bus区 别 on the school bus中的on可不可以用in来代替,in his father's car中的in 可否用on来代替 是in the bus ,in the train还是on the bus ,on the train?见题. 一项工程,甲单独做10天完成,甲乙工作效率比是3：2,如果甲乙两人合作几天完成? all good things -The Weepies下载地址! 英语翻译He was in the first third-grade class I taught at Saint Mary's School in Morris,Minnesota.All 34 of my students were dear to me,but Mark Eklund was one in a million.Very neat in appearance,he had that happy-to-be-alive attitude that made 一辆卡车后面用轻绳拖着质量为m的物体A,A与地面的摩擦不计,当卡车的加速度为g时,绳的拉力为多大?求指...一辆卡车后面用轻绳拖着质量为m的物体A,A与地面的摩擦不计,当卡车的加速度为g时, 一辆卡车后面用轻绳拖看质量为m的物体A,A与地面的摩擦力不计,求当卡车的加速度a＝g时,绳的拉力 一悬挂在汽车内的事物,m=0.4kg,在汽车加速度为7.5m/s2加速时,g=10m/s2,绳子的拉力为