$.$ Interaction $($if it occurs$)$ makes tests on the individual factors unreliable and comparisons more complicated $.$ Heres an example of interaction and one thing that can be done to get some general information. A company that runs ACT test$-$preparation courses is considering different formats and lengths for the course either traditional $($face$-$to$-$face$)$ or online, and either standard length$(30$ day$)$ or condensed $(10$ day$).$ They randomly assign each of $40$ clients $($who have agreed to participate in the experiment$)$ to one of the four combinations of length and type, and note the test score achieved, giving the data in columns C$19$ C$22($Person testscore$)$ C$19($Person$)$ is an index of the data file Act$7$F$24$data.mwx Note that C$24$ is not used in part a$,$ but is needed for for part b$).$ Test $($usual setup, conclusion in context$)$ for difference in mean score due to type of course, length of course, and interaction between type and length. Have Minitab print the means for type and length $***$and also for interaction type$*$length $***($this is unusual $-$ we want it for this problem you will also use it with Case study $2).$ What are your conclusions from this test $($three conclusions$)?$