You are instructed to perform a statistical test to find out if the "day of the week" influences the mean goods "delivery time". a. We could not reject the null hypothesis, the mean delivery time is not different for different day of the weekb. We reject the null hypothesis the mean delivery time is different at least on one of the days of the weekc. We accept the null hypothesis, the mean delivery time is not different for different days of the weekd. We reject the null hypothesis, the mean delivery time is different for every day of the week