若y=2x+1,当x( )时,y<x。
<-1
I told Mom that not everyone could manage to have 3 meals on time everyday, ________?
A.could he
B.didn't I
C.didn't she
D.could they
按轮碾法成型试件,试件放置时间不得少于()
A.6
B.12
C.24
D.48