静力学公理是将人类经过长期的观察和实验所积累的经验加以概括和总结而得出的结论，它的正确性可以在实践中得到（）。 ["证明","发展","推广","验证"]
已知，客户某周的投放数据为CPC=1.2，CTR=1.8%，ROI=1.3，请问CPM=？（） ["31.6","21.6","23.4","32.4"]
简述化学致畸作用机理。
Which two valid declarations of a char？（） [" Char ch = “a”；"," Char ch = ‘\\’ ‘；"," Char ch = ‘cafe’；"," Char ch = “cafe”；"," Char ch = ‘\\ucafe’；"," Char ch = ‘\\u10100’；"," Char ch = （char） true；"]
变换（Transformation）
简述诉讼证据的基本特征。
