For __________ (secure) sake, do not use the lift in the case of fire.

用例（Use Case）可以分成哪些层次？（）

一个Use Case是用户与计算机之间为达到某个目的的一次典型交互作用，作为结果，Use Case代表的是系统的一个完整功能。

中国大学MOOC: 用例（Use Case）可以分成哪些层次？（）

题目：统计RSH.dbf中职称是教授、副教授、讲师和助教的人数。P65 USE RSH ***********FOUND********** STORE 1 TO A , B , C , D DO WHILE .NOT.EOF DO CASE CASE 职称 = “教授” A = A + 1 CASE 职称 = “副教授” B = B + 1 CASE 职称 = “讲师” C = C + 1 CASE 职称 = “助教” D = D + 1 ENDCASE ***********FOUND********** NEXT 1 ENDDO USE ? A,B,C,D

_____ emphasizes on the sequence of messages between objects. A: use case diagram B: class diagram C: collaboration diagram D: sequence diagram

We make sure we’re always well stocked up with candles, just ________. A: in case B: for certain C: in practice D: for use

In MLA style, a publication of periodical publications appearing only on the web often does not have page numbers; if that is the case, use ___________ in place of page numbers.

中国大学MOOC: In the following use case diagram, which statement is wrong? _____在下面的用例图中，哪个语句是错误的？ _____

‏Which model does not belong to the object oriented analysis model?‍ A: use case modeling B: class modeling C: dynamic modeling D: ER modeling