25. 假設混凝土允許強度試驗結果低於fc’-35kgf/cm2之機率為1%,則目標平均強度fcr’=
(A)fc’-35+2.33σ
(B)fc’+1.34σ
(C)fc’
(D)1.15 fc’

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統計: A(989), B(227), C(100), D(94), E(0) #877828