目前常用（ ）对多媒体的到达率进行计算：多媒体达到率=a+b-(ab)
目前常用塞恩斯伯里方法对多媒体的到达率进行计算：多媒体达到率=a+b-(ab)
Lie detector is a device that helps determine whether a person is telling the truth. A lie detector, also called a polygraph
