串是任意有限个
A．符号构成的集合
B．符号组成的序列
C．字符构成的集合
D．字符构成的序列
参考答案：D
数据通信网服务器CPU利用率的运维指标为（）
A.大于80%
B.小于90%
C.小于80%
D.小于100%
Timmy was only 11 years old, but he is already 1.7 meters tall. He is too tall __________ his age, I think.
A．at
B．in
C．about
D．for
