A.fcu.0≥fcu.k+1.645α B.fcu.0=fcu.k+0.645α C.fcu.0=fcu.k+1.1α D.fcu.0=fcu.k+2α
A.23.0% B.25.5% C.22.0% D.20.0%
A.2640 B.2645 C.2650 D.不能判定