【单选题】Condition of self-lock for screw is .A.lead angle ≤ equivalent frication angleB.lead angle ≤ frication angleC.lead angle ≥ frication angle D.lead angle ≥ equivalent frication
A.
lead angle ≤ equivalent frication angle
B.
l ead angle ≤ f rication angle
C.
l ead angle ≥ f rication angle
D.
l ead angle ≥ e quivalent frication
【简答题】What 's the first camera angle ?
【判断题】The multiview projection method in China is first angle projection.
【简答题】什么是早期胃癌?并列举其肉眼和镜下的类型。
【单选题】In the navigational triangle,the angle at the elevated pole is the ______.