设,其中f(x)为连续函数,a>0且a≠1,则f(x)等于()。
A.2a2x
B.a2xIn a
C.2xa2x-1
D.2a2xln a
参考答案:D
下列实验操作正确的是( )
A.
点燃酒精灯
B.
测定溶液PH
C.
加热液体
D.
量取9.5mL液体
Memories of her staying with her host family in China often _____ to the mind of the Italian exchange student. [ ]
A. call up
B. hold back
C. bring up
D. come back