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?

Determine whether the question is a statistical question. explain. 1. what is the eye of sixth grade students? 2. at what temperature (in degree fahrenheit) does water freeze? 3. how many pages are in the favorite books of students your age? 4. how many hours do sixth grade students use the internet each week? you!