A:让发酵装置接受光照
B:给发酵装置适时排气
C:向发酵装置通入空气
D:将发酵装置放在45℃处
常温时,pH=14和pH=10的两种NaOH溶液等体积混合,所得溶液中c(H+)是( )
We haven't seen her for many days and there is ______ for her safety.
下面词语中,音形义有错误的一项是( )。