被除数和除数同时加上30,商不变.______.
被除数和除数同时加上30,商不变,
此说法错误,应该是被除数和除数同时乘(或除以)30,商不变,
故答案为:×.
Many children, _________ parents are away working in big cities, are taken good care of in the village.
A.their
B.whose
C.of whom
D.with whom
中学教材上介绍的干冰晶体是一种立方面心结构,如图所示,即每8个CO2构成立方体,且在6个面的中心又各占据CO2分子,在每个CO2周围距离0.707a的CO2有
A.4个
B.8个
C.12个
D.6个