A:①②③
B:①②④
C:①③④
D:②③④
⑴I'd like some noodles. ____
⑵Use the spoon. ____
⑶Pass me a bowl. ____
⑷The knife is on the table. ____
⑸Some chicken, please. ____
A. B. C.
D. E.
给出下列函数:①y=2x;②y=-2x+1;③y=2x(x>0);④y=x2(x<-1).其中,y随x的增大而减小的函数是( )