A.10‰ B.15‰ C.20‰ D.25‰
A.0.5~2mm B.1~3mm C.2~3mm D.3~4mm
A.斜段長(zhǎng)度 B.彎曲伸長(zhǎng) C.彎鉤增加 D.搭接長(zhǎng)度