A study about smoking and personality (by A. Terracciano and P. Costa, Addiction, vol. 99,2004, pp. 472-481 ) used a sample of 1638 adults in the Baltimore Longitudinal Study on Aging. The subjects formed three groups according to smoking status (never, former, current). Each subject completed a personality questionnaire that provided scores on various personality scales designed to have overall means of about 50 and standard deviations of about 10 . The table shows some results for three traits, giving the means with standard deviations in parentheses. Never Former Current smokers smokers smokers F (n = 828) (n = 694) (n = 116 Neuroticism 46.7(9.6) 48.5(9.2) 51.9(9.9) 17.77 Extraversion 50.4(10.3) 50.2(10.0) 50.9(9.4) 0.24 Conscientiousness 51.8(10.1) 48.9(9.7) 45.6(10.3) 29.42 a) For the F test for the extraversion scale, using the 0.05 significance level, what conclusion would you make? b) Refer to part a). Does this mean that the population means are necessarily equal