You are taking over a project and determine the following：Activity B has an early finish(EF)of day 3，a late finish(LF)of day 6，and an early start(ES)of day 2．Activity L is being done by a hard-to-get resource．The cost performance index(CPI) is 1.1 and the schedule performance index(SPI)is 0.8．Based on this information，what would you be more concerned about ？（）

A．Floa

B．Resource

C．Cos

D．Schedul

镗刀的楔角是指前刀面与后刀面之间的夹角，它主要影响（）。

A.刀尖强度

B.刃口的锋利程度

C.主切削刃参加工作的长度、切削厚度与切削宽度

D.切削热造成刀具热量的散发

E.进给力与背向力两者的分配比

F.刀具的使用寿命