求等差数列8,5,2，……的第20项

向量a=（4,3）,2a=（）

若直线m与直线n都垂直与平面α，则直线m与直线n的位置关系是（）。

在等差数列an中，a1=4，a2=6，求a4=（）

一个圆有无数条半径，这些半径都相等

与点（-2,1）关于y轴对称的点的坐标是（）。

下列函数中，（）是幂函数

已知一个直角三角形，一个角为60度，则另一个角为（）。

已知函数f(x)=4x是（）。

若直线m与直线n都垂直与平面α，则直线m与直线n的位置关系是（）

墙壁与地面所形成的二面角是（）

过程考核二（数列）：已知数列3,3,3,3……则数列的第n项为（）

过程考核一（三角函数）：求值tan45°=（）

过程考核三（平面向量）：向量a=（4,3）,向量b=（1,1）则a-b=（）

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