A.△y>dy>0
B.△y<dy<1
C.△y<dy<-1
D.△y>dy<2
[单选题]A.△y>dy>0B.△y<dy<1C.△y<dy<-1D.△y>dy<2
[单选题]A.△y>dy>0B.△y<dy<1C.△y<dy<-1D.△y>dy<2
[单选题]A.△y>dy>0B.△y<dy<1C.△y<dy<-1D.△y>dy<2
[单选题]A.△y>dy>0B.△y<dy<1C.△y<dy<-1D.△y>dy<2
[单选题]A.-6B.2C.3或-2D.-6或2E.3或-6
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