缺铁性贫血常见病因A．慢性肝炎 B．慢性胃炎 C．慢性溶血 D．慢性感染 E．慢性失

在某项存货年需用总量固定的情况下，每次订货数量越多，则( )。

A．订货成本总额越高

B．订货成本总额越低

C．储存成本总额越高

D．储存成本总额越低

E．存货总成本越低

根据下列语句，给“羌笛”下定义。（可增删词语）

①羌笛是一种民间竖吹乐器

②羌笛由两根竹管构成

③竹管长15至20厘米

④羌笛的管头插着竹簧

⑤竹管上有大小一致的洞孔

⑥两根竹管并在一起，且丝线缠绕

答：______________________________________________________

In low - speed network ,it is usually adequate to wait for congestion to occur and then react to it by telling the source of packets to slow down. In high - speed networks, this approach often works poorly, because in the (71) between sending the notification and notification arriving at the source, thousands of additional (72) may arrive. In ATM network , a major tool for preventing (73) is (74) control. When a host wants a new virtual (75) ,it must describe the traffic to be offered and the service expected.

A．flow

B．admission

C．traffic

D．time

头部CT检查常用______作为扫描基线

A．听眉线
B．听眦线
C．听眶线
D．听口线
E．听鼻线

事物发展的周期性体现了（）

A、事物发展的直线性与曲折性的统一

B、事物发展是一个不断地回到出发点的运动

C、事物发展的周而复始的循环性

D、事物发展的前进性和曲折性的统一