某建筑场地的抗震设防烈度为8度，设计基本地震加速度为0.30g，设计地震分组为第二组。场地覆盖层厚度为20m，土层等效剪切波速度为245m/s，结构自振周期为0.5s，阻尼比为0.04。试问：在计算水平地震作用时，相应于多遇地震的水平地震影响系数最接近下列（）项。（）

A.0.26

B.0.21

C.0.18

D.0.14

The purpose of the requirements definition phase is to produce a clear, complete, consistent, and testable (46) 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 (47) that it must meet. The starting point is usually a set of high-level requirements from the (48) that describe the project or problem.
In either case, the requirements definition team formulates an overall concept for the system and then defines (49) 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 (50) requirements for the system from the high-level requirements and the system and operations concept. Using structured or object-oriented analysis the team specifies the software functions and algorithms needed to satisfy each detailed requirement.

A．criterion

B．standard

C．scenarios

D．system