Consider the data with analysis shown in the following computer output: Level N A c D Source Groups Error Total 6 s 6 7 Mean 87.974 76.167 80.000 69.333 3 20 23 StDev 5.323 6.555 9.230 6.154 ss 116528 966.74 2132.02 MS 388.43 48.34 F 8.04 p 0.001 Is there sufficient evidence of a difference in the population means of the four groups? O Yes O No