13. Mrs. Carrico has been asked to determine the attitude of the students at her school toward a new dress code policy. She asks Paul, a member of the council who is taking AP Statistics, to send a questionnaire to an SRS of 100 students. Eighty-seven students return the completed questionnaire. Paul decides to randomly select 13 additional students to serve as replacement subjects to complete the sample of 100. Is Paul's sampling method appropriate? Briefly comment on the merits of this method or its pitfalls.