A:①③
B:②④
C:②③
D:①④
科研人员对某草原一种哺乳动物的种群进行研究,得出了与种群密度相关的出生率和死亡率的变化,如图所示。有关此图的叙述不正确的是
The doctor is skilled at treating heart trouble and never accepts any gift from his patients,so he has a very good_____.
She singing.
已知函数y=logax(a>0且a≠1),当x∈3,9时,函数的最小值比最大值小1,则a=____.