The number of applicants for a job is 15. (C) Calculate the number of different ways in which six applicants can be selected for interview. The six selected applicants are interviewed on a particular day. Calculate the number of ways in which the order of the six interviews can be arranged. Of the six applicants interviewed, three have backgrounds in business, two have backgrounds in education and one has a background in recreation. Calculate the number of ways in which the order of the six interviews can be arranged, when applicants having the same background are interviewed successively. (C)