CREATE TABLE table_1566852_6 (interview_subject VARCHAR2, centerfold_model VARCHAR2)

How many total interview subjects wererthere when the centerfold model was Tamara Witmer?
SELECT COUNT(interview_subject) FROM table_1566852_6 WHERE centerfold_model = "Tamara Witmer"
SELECT COUNT("interview_subject") FROM "table_1566852_6" WHERE "Tamara Witmer" = "centerfold_model"