3. let n = {0, 1, ,9, 10} consider a relation r on nx n defined by (a, b) r (x, y) iff a + y = b + x i) prove that r is an equivalence relation. ii) describe the equivalence classes geometrically. iii) describe the quotient set nxn/r. iv) what is the index of r?

Which term best describes the association between variables a and b? no association a negative linear association a positive linear association a nonlinear association a scatterplot with an x axis labeled, variable a from zero to ten in increments of two and the y axis labeled, variable b from zero to one hundred forty in increments of twenty with fifteen points in a positive trend.