A manufacturer of energy bars is testing 4 of their new flavours: red rage(R) which harvests the power of goji berries; blue bonanza(B) which is packed full of blueberries; green groove(G) which utilizes the super food Kale; and white wonder(W) which is choc full of white chia seeds. Thirty bars of each are sent to a lab to test for fat content (in g).

A statistician was asked to analyse the data using ANOVA methodology, some of which is presented below.Unfortunately she was not able to complete the analysis and you have been asked to answer the questions below, which primarily concern finding the energy bar with the lowest mean fat content.

> summary (AnovaModel.1) Df Sum Sq Mean Sq F value Pr(>F) colour 3 78.47 26.155 30.38 1.45e-14 *** Residuals 116 99.89 0.861 Signif. codes: 0 *** 0.001 '** 0.01 '* 0.05 !' 0.1 "'1 > with(energy, numSummary(fat, groups = colour, statistics = c("mean", mean sd data:n B 9.044371 0.9417587 30 G 10.645709 0.7716196 30 R 10.335671 0.8407149 30 W 8.758037 1.1203592 30 Multiple Comparisons of Means: Tukey Contrasts Fit: aov(formula = fat ~ colour, data = energy) Linear Hypotheses: Estimate Std. Error tvalue Pr(>|t)) G - B ==0 1.6013 0.2396 6.684 leveneTest( score ~ make, data = cars, center = "median") Levene's Test for Homogeneity of Variance (center = "median") Df F value Pr(>F) group 3 1.1662 0.3258 116