A.mfcu≥fcu,k+0.7σfcu,min≥fcu,k-0.7σ; B.mfcu≥fcu,k+0.8σfcu,min≥fcu,kk-0.8σ; C.mfcu≥fcu,k+0.85σfcu,min≥fcu,k-0.85σ; D.mfcu≥fcu,k+0.95σfcu,min≥fcu,k-0.95σ。
A.1mm; B.0.5mm; C.5mm; D.10mm。
A.兩個直徑之差35mm; B.兩個直徑之差55mm; C.兩個直徑之差45mm; D.兩個直徑之差25mm。