对于不能替代使用的存货、为特定项目专门购入或制造的存货以及提供劳务的成本，通常采用（）确定发出存货的成本。

A．个别计价法

B．先进先出法

C．移动力盯权平均法

D．加权平均法

Electronic computers (), the complicated mathematical operations, such as weather forecast and the control of satellites, can be done quickly and accurately.

A. being used

B. used

C. having been used

D. to be used