用物理学上的分子运动阐述油品蒸发损耗的物理过程
参考答案:
液面处油品蒸发产生油蒸汽,油蒸汽进入油罐的上部气体空间,与空气组成混合物,当外界条件变化时,油气混合物排出油罐!
Some scientists think that it may take _________years to make robots look like people, and do the same things as us.
A. hundreds of B. two hundreds of C. two hundreds
木、竹面层铺设在水泥类基层上,其基层表面应坚硬、平整、洁净、不起砂,表面含水率不应大于()%。
A.4
B.6
C.8
D.10