Give an example of a random phenomenon that would be studied by (i) a physicist, (ii) a geneticist, (iii) a traffic engineer, (iv) a quality-control engineer, (v) a communications engineer, (vi) an economist, (vii) a psychologist, (viii) a sociologist, (ix) an epidemiologist, (x) a medical researcher, (xi) an educator, (xii) an executive of a television broadcasting company.