短語詞組短語frequency cumulative distribution curve 頻率累積分佈曲線frequency -distribution curve 頻率分佈曲線Bellshaped frequency distribution curve 正態(tài)分佈hydrologic frequency distribution curve 水文頻率分佈曲線size -frequency distribution curve of particle [土壤]粒逕頻率分配曲線curve frequency distribution 頻率分佈曲線distribution of frequency curve 頻率曲線分佈 返回 frequency distribution curve