国外建设工程项目投资设想阶段投资估算的误差率范围为( )左右。

A．±5%

B．±10%

C．±20%

D．±30%

An example of scope verification is （）.

A.review the performance ofan installed software module

B.managing changes to the project schedule

C.decomposing the WBS to a work package level

D.performing a benefit/cost analysis to determine if we should proceed with the project