小儿面呈白色，可出现在以下何种病证？（）
A.呕吐
B.疳证
C.寒证
D.虚证
E.泻泄
参考答案：A, B, C, D, E
半导体激光器（LD）有哪些特性？
(74) is a complex consisting of two or more connected computing units, it is used for the purpose of data communication and resource sharing。
A．Computer network
B．Computer device
C．Computer processor
D．Computer storage
