A.防雨 B.防潮 C.防沖擊 D.A+B+C
陶瓷錦磚的密度為()g/cm3.
A.2.3-2.4% B.2.5-2.6% C.2.6-2.7% D.2.7-2.8%
A.6% B.4% C.2% D.1%