A:水
B:钙盐
C:钠盐
D:尿素
把4米长的绳子平均分成5段,每段长是全长的____,每段长____米.
若曲线C1:x2+y2﹣2x=0与曲线C2:y(y﹣mx﹣m)=0有四个不同的交点,则实数m的取值范围是( )
Look, there is ________ onion in the kitchen. We can cook it for dinner.