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My Schoolbag
I have a big schoolbag. It's blue. It's got a lovely white rabbit on it. It's got four pockets. There are so many books in it. It's very heavy. It's old and broken,but I like it very much.
物质X是一种重要的阻燃剂,工业上用三氧化二锑Sb2O3生产X的化学方程式为:Sb2O3+2H2O2═X+2H2O.根据质量守恒定律,推断X的化学式为( )
如图有下列仪器,在实验中使用仪器的说法错误的是( )
一个物体以v0=16m/s的初速度冲上一光滑斜面,加速度的大小为8m/s2,冲上最高点之后,又以相同的加速度往回运动.则( )