下面各组的两个比不能组成比例的是( )
A:7:8和14:16
B:0.6:0.2和3:1
C:19:110 和10:9
阅读理解A
Millie:I usually ride my bike to schoo1.It takes me about twenty minutes.Sometimes,my father drives me to school in his car.
ff:My sister Mona and I like running to school.Running is good for us.Usually we leave home at half past seven.Then we get to school at seven fifty.
Alice:I don't like getting up early in the morning.So I have no time for breakfast at home.I usually have it on the school bus.I like my is ride because in the thirty minutes,I can eat my breakfast and walk with my friends.
Mike:My home is ten kilometers from my school.Every morning I
get up early.After breakfast l walk to the subway station.That
takes about ten minutes.Then I take the subway to school.It takes
twenty minutes.
如果关于x的方程2-xx-5=m5-x无解,则m等于( )
“秦朝以前,官吏和私人的印章均可称玺,至秦朝,只有天子的印才能叫玺,而且用玉制作,群臣不敢再用。”这一现象反映的本质是( )。