Which of the following statements about the one-way ANOVA table is(are) true?

A) Sums of squares represent variation present in the data, and they are calculated by summing squared deviations.

B)There are three distinct sources of variation represented in the table: groups, error, and total.

C)The sum of squares for total(SST) is composed of two parts, one due to groups(SSG) and one due to error(SSE)

D)Mean squares are calculated by dividing the corresponding sum of squares by its degrees of freedom.

E) All of the above.