信息系统由哪几类要素组成？
参考答案：五要素：人、硬件、软件、数据、处理规程。
6-磷酸果糖激酶-1的别构抑制剂是
A．6-磷酸果糖
B．1，6-二磷酸果糖
C．柠檬酸
D．乙酰CoA
E．AMP
My teacher prefers music _____ quiet and gentle. [ ]
A. that are
B. that is
C. which has
D. whose is
