You are looking at Summary Statistics for the amount of time it takes to install a furnace. You have concluded that the times to completion are distributed symmetrically. Your boss has asked you if there is a lot of variability in the times. You would say there is a lot of variability if a. the standard deviation divided by the mean is more than .5b.(Q3-Q1)/Median is more than .5 c.(Q3-Q1)/Mean is more than .05d. the mean divided by the standard deviation is greater than .5