下列试验中哪项试验可区别沙门菌与志贺菌()
A.尿素分解试验
B.动力试验
C.甲基红试验
D.甘露醇发酵试验
E.枸橼酸盐利用试验
参考答案:B
设等差数列{an}的前n项之和为Sn,已知a2=3,a5=9,则S5等于( )
A.15
B.20
C.25
D.30
The term “__( )__ program” means a program written in high-level language.
A.compiler
B.executable
C.source
D.object