A.轻、中、重三个级别 B.轻、重、特重三个级别 C.轻、中、重、特重四个级别
A.1 B.1.25 C.1.5 D.2
A.1 B.2 C.3 D.4
A.同向捻 B.交互捻 C.混和捻
A.3% B.5% C.7% D.10%