Documentation of a software package is normally produced for two purposes.One is to explain the （） of the software and describe how to use them.This is known as （）because it is designed to be read by the user of the software.The other purpose of documentation is to describe the software’s internal composition so that the system can be maintained later in its lifecycle.Documentation of this type is knownas （）.

One is to explain the （） of the software and describe how to use them.

A．plans

B．cost

C．features

D．schedules

在相同保险金额、相同投保条件下，人寿保险中保费最低的是()。

A．(A) 终身死亡保险

B．(B) 定期死亡保险

C．(C) 年金保险

D．(D) 两全保险