It’s___(reasonable)toexpectpeopletoworkmorethan60hoursaweek.
两列机械波I、II在传播过程中遇到一障碍物,I的波长与障碍物尺寸相当,II的波长远小于障碍物尺寸,则机械波()
InAugust1977,asatellitetogatherdataaboutthe10millionblackholeswhicharethoughttobeintheMilkyWay.
在双缝干涉实验中,屏幕上P处是暗条纹,则两束相干光在P处的光程差可能是()
Thetheoryofblackholesinspace__(accept)bymanyseriousscientistsandastronomers.