Consider the data with analysis shown in the following computer output: Level N Mean StDev 7 85.145 5.602 B 5 76.167 6.555 L 5 80.000 9.230 D 7 69.333 6.154 Source DF SS MS F P Groups 3 916.08 305.36 6.58 0.003 Error 20 928.17 46.41 Total 23 1844.25 What is the pooled standard deviation? What degrees of freedom are used in doin means? Round your answer for the pooled standard deviation to two decimal places. The pooled standard deviation is i degrees of freedom