A.砂子50%~60%,石灰34%~50% B.砂子70%~78%,石灰22%~30% C.砂子88%-90%,石灰10%~12% D.砂子80%~86%,石灰14%~20%
A.l B.2 C.3 D.4
A.±2mm B.±4mm C.±5mm D.±7mm