A.柱邊長-保護層*2+1.9d*2 B.柱邊長-保護層*2+max(75,10d)*2 C.柱邊長-保護層+1.9d*2+max(75,10d)*2 D.柱邊長-保護層*2+1.9d*2+max(75,10d)*2