A:稳定性:H2S>HF
B:HCl的电子式为
C:一个D2O分子所含的中子数为8
D:在卤化氢中HF最稳定
设函数fx=ex+x-2,gx=lnx+x2-3,若实数a、b满足fa=0,gb=0,则( )
Shelly had prepared carefully for her biology examination so that she could be sure of passing it at her first ________.( )