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【判断题】

硬质合金螺纹车刀的背前角取0°,高速车螺纹时,它的牙型角必须磨成60°。

A.
正确
B.
错误
举报
参考答案:
参考解析:
.
刷刷题刷刷变学霸
举一反三

【单选题】梯形螺纹车刀的进给方向后角为()。

A.
(3°~5°)+ψ
B.
(3°~5°)-ψ
C.
(5°~8°)+ψ
D.
(5°o~8°)-ψ

【单选题】Passage Two Questions 66 to 70 are based on the following passage: If an agreement signed in Germany works out, travelers of this Asian city may one day be able to move from the downtown area to its n...

A.
It is difficult to see fingerprints with human eyes.
B.
There are special ways to recover a suspect’s fingerprints.
C.
Even a small part of a fingerprint is useful for identification
D.
Suspects usually try to avoid leaving their fingerprints at the scene.