A company repairs desktop calculators and cash registers. The data from 18 repairs are written in the table. Each repair has 2 important sets of data. The first one is a number of repaired calculators (X) and the second one is a total repair time (Y). Couple Repaired calculators (X) |Total repair time (Y). 1 7 97 2 86 3 UT 78 4 10 5 UI 75 6 62 7 101 8 39 9 53 10 33 Sum = 44 634 a) Is there a correlation between the number of repaired calculators and the repair time ? Show this statistically. b) Calculate the regression equation for the total repair time with the number of repaired calculators. c) Estimate the total repair time if the number of repaired calculators is 8