①周天子威望下降
②诸侯不再听从周天子的命令
③诸侯之间经常进行争霸战争
④最终秦国完成国家统一
A:①③④
B:①②③
C:①②④
D:②③④
函数fx=x-1x+1设f1(x)=f(x),f2x=ff1x,﹒﹒﹒fnx=ffn-1x,(x∈N+,N≥2),令集合M={x∣f2008x=x2,x∈R}则集合M为( )
Do you like spring ?
No , .
⑴Where is the eraser? ____
⑵Where are the crayons? ____
⑶Put your book on your desk. ____
A.OK!
B.It's under your pencil box.
C.They're in my hand.