已知直线l1:2x+y﹣1=0,直线l2经过点A(﹣2,m)和点B(m,4),
(I) 若l1∥l2,求实数m的值;
(Ⅱ) 若点A、B分别在直线l1的两侧,求实数m的取值范围.
解:( I)∵直线l1:2x+y﹣1=0的斜率为﹣2,
若l1∥l2,则kAB=4-mm+2
在同一平面上,若∠BOA=70°,∠BOC=15°,则∠AOC=____ .
甲乙两队用一根轻绳进行拔河比赛,结果甲队获胜,则在比赛过程中( )
A single-parent child should have the right to enjoy normal parental love from both just as his other peers, which some psychologists see as _____to their emotional well-being.