什么叫门到门发货？

在数列{a_n}中，a₁=1，a_n+1=a_n+2，则a₁与a₅的等比中项为（　　）

A．3

B．-3

C．±3

D．±9

受精卵受到照射的效应表现为显性致死性效应的时间是（）。

A.着床前期

B.器官形成期

C.胎儿期

D.着床后期

E.胚胎期

下列句子中划线词语运用有误的一项是[ ]

A．同学们在日常学习中，应该有滴水穿石的精神。

B．幼儿园的孩子提前学习小学课程的拔苗助长式的做法，已受到许多有识之士的批评。

C．小明建议初三（1）班与（2）班进行一次篮球比赛，大家随波逐流，纷纷表示赞同。

D．在去年这场特大雪灾面前，党的领导发挥了中流砥柱的作用。

早在南宋时期，注重耕读的朱熹，将自己的儿子送到当地的书院就学，并赋诗《送子入板桥桐江书院勉学诗》。要求根据上联，补全下联，你认为最恰当的是（　　）。

上联：汝若问儒风，云窗雪案深功夫。  

下联：汝若问农事，          。

A．绿阴冉冉遍天涯

B．欸乃一声山水绿

C．万古荒凉楚水西

D．晓烟春雨劳耕锄

The primary advantages of a Client/Server system arise from splitting the processing between the client system and the database server. Since the bulk of the database processing is done on the back-end, the speed of the DBMS isn’t tied to the speed of the (31) .

The major disadvantage of Client/Server system is the increased cost of (32) and support personnel who maintain the database server. There is also the issue of (33) with so many parts comprising the entire C/S system; Murphy’s Law can kick in-the more pieces that compose the system, the more pieces that can fail. It’s also harder to track down problems when the system (34) . And it can initially take longer to get all the components set up and working together. All this is compounded by the general lack of experience and expertise of potential support personnel and programmers, due to the relative newness of the technology. As C/S system become more common, this problem should abate.

Therefore the C/S system is more (35) .

（34）是（）

A.burns

B.crashes

C.runs

D.uses