如果两条平行线被第三条直线所截,那么一组同位角的平分线[ ]
A.互相平行
B.互相垂直
C.交角是锐角
D.交角是钝角
答案:A
_____ his homework, he went out to play.
A.Having done
B.Done
C.He has done
D.He had done
若某一组数进栈的序列为123456,则该组数的出栈序列 (58) 是436512; (58) 是132465。