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3 To explain the percent of variation of y in a relationship between x and y. A Give the complete formal name. B Write the formula for the c-prediction interval. 4 To determine whether a frequency distribution fits an expected distribution. A Give the complete formal name. B What kind of experiment could input to this distribution comparison ? 5 To test the independence of two variables. (Observed frequencies obtained using random sampling, each expected frequency greater than or equal to 5.) A Give the complete formal name. B What is the formula for the degrees of freedom