东北平原的作物熟制为

有两组物质：①组CH₄、聚乙烯、邻二甲苯  ②组2﹣丁烯、乙炔、苯乙烯下列有关上述有机物说法正确的是

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    Tom always can't sleep well at night. But he was never late for work. He went to see his doctor on Sunday afternoon. He took the subway to get there. He met his boss on the subway and they talked for a while.

    Tom got some sleeping pills from the doctor. That night Tom took the pills. He had a nice sleep. He went to work happily on foot in the morning. Getting into the office, he said to his boss “I had a nice sleep and got up happily this morning.” “That's fine,” shouted the boss, “but where were you on Monday?”