A.1~2 B.1.5~2.5 C.2~4 D.2.5~4.5
A.鉛60%,錫40% B.鉛錫各50% C.鉛75%,錫25% D.鉛80%,錫20%
A.0°~90° B.0°~~180° C.0°~270° D.0°~360°