Telemarketers often follow a pre$-$written script when interviewing customers. A manager of a major telemarketing company would like to compare the effectiveness of three different sales scripts, Script A$,$ Script B$,$ and Script C$.$

An investigator performed an experiment in which $32$ telemarketing trainees were randomly assigned to three groups: the first consisting of $11$ trainees, the second $12$ trainees, and the third $9$ trainees. Trainees in the first group were trained to market their products using Script A$,$ trainees in the second group were trained to use Script B$,$ and trainees in the third group were trained to use Script C$.$ After training, each trainee$$s sales amount over a one$-$week period was recorded.