氮及其化合物的“价类二维图”如图所示。(1)A点对应的物质可以是 (填字母)。a.氮气b.氧气c.氢气(2)B点对应物质的化学式是 (填字母)。a.N2Ob.N

氮及其化合物的“价类二维图”如图所示。(1)A点对应的物质可以是 (填字母)。a.氮气b.氧气c.氢气(2)B点对应物质的化学式是 (填字母)。a.N2Ob.NOc.N2O3(3)NH3•H2O的物质

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—_____________ you in the kitchen, Tom? ( ) —Yes, I am.

—_____________ you in the kitchen, Tom? ( ) —Yes, I am.

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you, did, do, else, anything (?)

you, did, do, else, anything (?)

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My sister ______ (喜欢吃糖果), so she is a little fat.

My sister ______ (喜欢吃糖果), so she is a little fat.

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