命题“对任意的x∈R，x³﹣x²+1≤0”的否定是（　　）

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    Do you know a kind of bird called tawny owl? Where does it come from? It comes from Finland (芬兰). What color is it? It is brown. Are all the tawny owls brown? No. Tawny owls come in two colors: pale gray and brown. And in Finland, it often snowed in winter. Many tawny owls were pale gray. But as the Finnish (芬兰的)winters get warmer, there are more brown ones. Why is that?

    The University of Helsinki team tries to study tawny owls. They find that tawny owls get the color from their parents. The gray owls could get food easily in the snow in the past. But now the winter is warmer. There is little snow so the brown owls can live well, too. The number of the owls is getting bigger.

    The leader of the team, Dr Patrick Karell, said that the birds change their color to meet the weather. We are sure the weather change can do something to the animals.

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