She hardly ever eats （） potatoes. A.bread

取得（）的人员，经注册后方可以物业管理师的名义执业。

A.《物业管理师合格证书》

B.《物业管理师资格证书》

C.《物业管理师注册证》

D.《物业服务企业经理上岗证书》

In low-speed network，it is usually adequate to wait for congestion to occur and then react to it bytelling 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 offeredand the service expected．

（71）处填（）。

A．interval

B．time

C．slot

D．delay

现代企业制度的保证是（）

A.企业产权制度

B.有限责任制度

C.现代公司制度

D.科学管理制度

壳管式冷凝器要定期清除水垢。（）

心脏震颤是怎样产生的？有何临床意义？