中碳钢和高碳钢取残余变形( )的应力作为屈服强度。
A．0.2%
B．0.5%
C．1%
D．2%
参考答案：A
固定下颌角，防止下颌过度向前移动的韧带是（）。
A.髁下颌韧带
B.蝶下颌韧带
C.翼下颌韧带
D.茎突下颌韧带
The concept of the （） states that changes related to one requirement-scope，time or cost will at least influence one other element．
A．three-point estimation
B．triple constraint
C．three wise men
D．three needs theory
