当采用S型曲线比较法时，如果实际进度点位于计划S型曲线左侧时，则该点与计划S曲线的垂直距离表示（）；该点与计划S曲线的水平距离表示（）。

该点与计划S曲线的水平距离表示（）。

单项选择题Configuration management is the process of managing change in hardware，software，firmware，documentation，measurements，etc．As change requires an initial state and next state，the marking of significant states within a series of several changes becomes important．The identification of significant states within the revision history of a configuration item is the central purpose of （） identification.

A．baseline
B．value
C．cost
D．control

单项选择题The standard (IEEE 802)format for printing （） in human-friendly form is six groups of two hexadecimal digits，separated by hyphens(-) or colons(:)，in transmission order, e.g.01-23-45-67-89-ab，01:23:45:67:89:ab．This form is also commonly used for EUI-64.

A．hard disk logical block address
B．IP address
C．mail address
D．MAC address