CREATE TABLE table_name_81 (size VARCHAR, ihsaa_class VARCHAR, previous_conference VARCHAR)

What is the size of the team that was previously from Central Indiana conference, and is in IHSSA Class 4a?
SELECT size FROM table_name_81 WHERE ihsaa_class = "4a" AND previous_conference = "central indiana"
SELECT "size" FROM "table_name_81" WHERE "4a" = "ihsaa_class" AND "central indiana" = "previous_conference"