在水平管道内,物料能输送是因为受到以下()等力的作用。
A、紊流气流垂直方向分速度产生的力;
B;空气的推力;
C、颗粒形状不规则所引起的空气作用力的垂直分力。
参考答案:A, C
--- Not everything that is best for nature is good for people.
--- Yes, would anyone say that economic development should be stopped ______ nature?
A.in need of
B.in fear of
C.in favor of
D.in honor of
纵向接缝是根据路面宽度和施工建筑宽度设置。一次铺筑宽度( )时,应设置带拉扦的假缝形式的纵向缩缝,纵缝应与线路中线平行。
A.大于3.5m
B.小于3.5m
C.大于4.5m
D.小于4.5m