安装内螺纹镗刀时，要使牙型角的角平分线与螺纹升角保持一致。
A. 正确
B. 错误
Which one is not important for your safety on board ship?（）
A. know where the lifejacket is stowed
B. know where the life-saving craft are fitted on the ship
C. know the escape routes
D. Good professional knowledge
从现代科学的角度分析将阿司匹林制成钙盐，是否能降低胃肠道的副作用？
用资产组合理论解释一国经常项目发生盈余后，该国货币汇率的变化情况。
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