单项选择题
A.体中线偏患侧1cm B.内切线的铅丝处 C.内切线的铅丝外1cm D.内切线的铅丝内1cm E.体中线偏健侧0.5cm
A.310° B.230° C.130° D.210° E.140°
A.1cm B.1.5~2cm C.2.1~2.5cm D.3cm E.0.5~1cm