坡屋顶是指屋面坡度在()以上的屋顶。
A. 5%
B. 10%
C. 15%
D. 20%
防水材料如尺寸较小,接缝必然就较多,容易产生缝隙渗漏,因而屋面应有较大的排水坡度,以便将屋面积水迅速排除。
A. 对
B. 错
Sustainable development is a matter of top ___ to the Chinese government.
A. conflict
B. concern
C. contact
D. conference
It indicates that China is seeing science as ___ to its future well-being.
A. efficient
B. unique
C. critical
D. alternative