A:由水电离的c(OH-)=10-14 mol/L的溶液:S2-、HCO3-、Na+、K+
B:K+、NH4+、NO3-、CO32-
C:K+、SiO32-、NO3-、Fe3+
D:pH = 2的溶液:Fe2+、NH4+、Cl-、NO3-
The little child was not old enough to __________ himself.
下列生物的生殖过程中,能发生可遗传变异的是( )
— Yes. She is ____ exchange student from America.