直方图的平均值和标准差怎么算

简介：As Bi Maokang's nephew, he thinks about Suifa Gun every day. Bi Denhan's familiarity with Suifa Gun is not as good as that of his uncle. After receiving the prince's order, he skillfully loaded the gunpowder, raised the gun, took a brief aim, and with a bang, the wooden target eighty steps away was smashed into pieces.