A.30s B.60s C.90s D.120s
A.1.05 B.1.10 C.1.25 D.6d
A.粗砂或细砂均可，15% B.中砂，15% C.粗砂或细砂均可，10% D.中砂，10%
A.不变 B.不一定 C.越大 D.越小
A.65℃~70℃ B.75℃~80℃ C.105℃~110℃ D.110℃~120℃
