Instruction 11-2
an Airline Wants to Select a Computer Software

Instruction 11-2
An airline wants to select a computer software package for its reservation system.Four software packages (1,2,3,and 4) are commercially available.The airline will choose the package that bumps as few passengers as possible during a month.An experiment is set up in which each package is used to make reservations for five randomly selected weeks.(A total of 20 weeks was included in the experiment. ) The number of passengers bumped each week is obtained,which gives rise to the following Microsoft
$$\begin{array}{l}\text { ANOVA }\\\begin{array} { | l | l | l | l | l |l| l | } \hline \text { Source of Variation } & \text { SS } & d f & \text { MS } & F & P \text {-value } & F \text { crit } \\\hline \text { Between Groups } & 212.4 & 3 & & 8.304985 & 0.001474 & 3.238867 \\\hline \text { Within Groups } & 136.4 & & 8.525 & & & \\\hline & & & & & & \\\hline \text { Total } & 348.8 & & & & & \\\hline\end{array}\end{array}$$
-Referring to Instruction 11-2,the within groups degrees of freedom is

A) 19.
B) 4.
C) 16.
D) 3.