A.次日,3,破環(huán)磁條 B.次日,4,破環(huán)磁條 C.當(dāng)日,3,沿磁條對(duì)角線剪角作廢 D.當(dāng)日,4,沿磁條對(duì)角線剪角作廢
A.30 B.60 C.90 D.100
A.15 B.10 C.5 D.3