Exhibit 7-11: in a 2 $\times$ 3 Experimental Design Three Kinds of Treatments (A, B, and Kinds

Exhibit 7-11: In a 2 $\times$ 3 experimental design three kinds of treatments (A, B, and C) were used with two groups of subjects (M and N) .The number of subjects and the mean of each group are as follows:
$\begin{array}{lll}&&&\text { Treatments }\\&&\mathrm{A} & \mathrm{B} & \mathrm{C} \\&\mathrm{~M}&\mathrm{X}=20 & \mathrm{X}=18 & \mathrm{X}=16 \\&&\mathrm{~N}=5 & \mathrm{~N}=5 & \mathrm{~N}=5 \\\text { subjects } \\&\mathrm{~N}&\mathrm{X}=12 & \mathrm{X}=14 & \mathrm{X}=16 \\&&\mathrm{~N}=5 & \mathrm{~N}=5 & \mathrm{~N}=5\end{array}$
The following is the incomplete summary table of multifactor analysis of variance.Complete the table and answer the following questions.
$\begin{array}{ll}\text { Source of variation } & S S & \underline { \text { df }} & \underline { \text { MS}} & \underline { \text { F}}\\\hline \text { Between columns } & 0 \\\text { Between rows } & 120 \\\text { Interaction } & \\\hline \text { Between groups } & 200 \\\text { Within groups } & \\\hline \text { Tntal } & 454\end{array}$
-Refer to Exhibit 7-11.The number of degrees of freedom for interaction is

A) 1.
B) 2.
C) 5.
D) 24.