物质的分类是学习化学需培养的重要能力之一，请对下类物质进行合理分类

①干冰 ②冰水混合物   ③医用75%的酒精   ④氢气  ⑤纯净的液态空气  ⑥矿泉水⑦过氧化氢溶液⑧木炭⑨二氧化锰⑩用高锰酸钾制取氧气后的生成物六种物质，其中属于混合物的有（填序号，下同）____，属于纯净物的有____．属于氧化物的有____属于化合物的有____．

处于有丝分裂过程中的动物细胞，某一时期细胞内的染色体数、染色单体数、 DNA 分子数之间的比例为 1 : 2 : 2 时，细胞内可能发生着

    Many people like spring, because they can go out and do many kinds of activities. We made a survey about the activities that people like to do in spring. Here are the results.
Scott：
    In spring, I often visit my uncle and I like fishing with him. I also like boating and enjoy the beach. Last spring my uncle and I went boating. The dolphins came so close to us. It was very amazing. I hope that I can go there again soon.
Linda:
    My favorite spring activity is gardening (园艺). I think it is relaxing to work in the garden. I grow many flowers in my garden every year. They are so beautiful.
Nancy：
    I love spring. I love going to the beach and spending a whole day there. It is so relaxing to lie on the beach. I also like surfing in the sea.
James：
    I am twelve years old. My favorite spring activity is swimming. I started to learn swimming when I was seven years old. I always have a good time with my friends in the river.

We went right round to the west coast by ______ sea instead of driving across ______ continent.

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