算术平均值公式简介：After lying on the grass for a while, Qin Fen called Qin Meier's intelligent optical brain: Meier, how are you and Sister Xiaoyan doing? Do you adapt to life there?
After lying on the grass for a while, Qin Fen called Qin Meier's intelligent optical brain: Meier, how are you and Sister Xiaoyan doing? Do you adapt to life there?
