建设（）是共享优质资源、降低培训成本的重要手段。
A.学习环境
B.专题课件
C.系列课件
D.远程教育网络
参考答案：D
上消化道出血患者出现黑便，估计其出血量为（）
A.>5ml
B.50～100ml
C.250～300ml
D.400～500ml
E.>1000ml
Open Shortest Path First(OSPF)is a (71) routing algorithm that (72) work done on theOSI IS-IS intradomain routing protocol. This routing, as compared to distance-vector routing,requires (73) processing power. The (74) algorithm is used to calculate mutes. OSPFrouting table updates only take place when necessary, (75) at regular intervals.
A．more
B．less
C．same
D．most
