The director of the riley​ county, kansas, library system would like to forecast evening patron usage for next week. below are the data for the past 4​ weeks: mon tue wed thu fri sat week 1 210 178 250 215 160 180 week 2 215 180 250 213 165 185 week 3 220 176 260 220 175 190 week 4 225 178 260 225 176 190 ​a) calculate a seasonal index for each day of the week ​(enter your responses rounded to three decimal​ places).