A.fcu,0=fcu,k+1.645δ B.fcu,0=fcu,k+1.56δ C.fcu,0=fcu,k+1.85δ D.fcu,0=fcu,k+1.45δ
A、>4.5 B、>4.75 C、>4.85 D、>4.95
A.1:0.6:0.8 B.1:0.5:0.8 C.1:0.2:0.4 D.1:0.6:0.3