The variability in the amount of impurities present in a batch of chemical used for a particular process depends on the length of time the process is in operation. a manufacturer using two production lines, 1 and 2, has made a slight adjustment to line 2, hoping to reduce the variability as well as the average amount of impurities in the chemical. samples of 25 measurements from each line yielded means and variances for the level of impurities as follows: line 1: mean = 3.2 variance = 1.04 line 2: mean = 3.0 variance = 0.51 a) do the data present sufficient evidence to indicate that the variance in the level of impurities of line 2 is lower than for line 1? test using a = 0.01 b) would you recommend making the adjustment to line 1 as well?