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To detect the presence of harmful insects in farm fields, we can put up boards covered with a sticky material and examine the insects trapped on the boards. Which colors attract insects best? Experimenters placed six boards of each of four colors at random locations in a field of oats and measured the number of cereal leaf beetles trapped. Here are the data: \(^{9}=\) III BEETLES (a) Is there evidence that the colors differ in their ability to attract beetles? Use ANOVA to answer this question and state carefully the conclusion from this ANOVA. (b) How many pairwise comparisons are there when we compare four colors? (c) Which pairs of colors are significantly different when we require significance level \(5 \%\) for all comparisons as a group? In particular, is yellow significantly better than every other color?

Many states require schoolchildren to take regular statewide tests to assess their progress. Children with learning disabilities who read poorly may not do well on mathematics tests because they can't read the problems. Most states allow "accommodations" for learning-disabled children. Randomly assign 100 learning-disabled children in equal numbers to three types of accommodation and a control group: math problems are read by a teacher, math problems are read by a computer, math problems are read by a computer that also shows a video, and standard test conditions. The researcher would like to compare the mean scores on the state mathematics assessment.