The purpose of the requirements definition phase is to produce a clear, complete, consistent, and testable (6) of the technical requirements for the software product. During the requirements definition phase, the requirements definition team uses an iterative process to expand a broad statement of the system requirements into a complete and detailed specification of each function that the software must perform and each (7) that it must meet. The starting point is usually a set of high level requirements from the (8) that describe the project or problem.
In either case, the requirements definition team formulates an overall concept for the system and then defines (9) showing how the system will be operated publishes the system and operations concept document and conducts a system concept review(SCR).
Following the SCR, the team derives (10) require merits for the system from the high level requirements and the system and operations conceptusing structured or object-oriented analysis, the team specifies the software functions and algorithms needed to satisfy each detailed requirement.

A．function

B．definition

C．specification

D．statement

古诗“花气袭人知骤暖”， 从花的芳香气味变浓可以知道周边的气温突然升高。从物理学的角度分析，这是因为温度越高，                                。汽车的发动机选用水做冷却剂，主要是由于水的　　　     的缘故．烈日下，操场上单杠的温度会升高，这是通过　　　　        的方式改变其内能的。