——Do you know ______ woman in blue? --- Yes. She is my maths teacher.
A:the
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C:an
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用秦九韶算法求多项式f(x)=5x5+2x4+3.5x3﹣2.6x2+1.7x﹣0.8,当x=1时的值的过程中v3=____ .
读《桃花源记》,写出描写桃花源中人们和平劳动和幸福生活的语句:
如图,△ABC的顶点都是正方形网格中的格点,则cos∠ABC等于( )