Bryant Heating เข้าในปีใด?ไม่จำเป็นต้องใช้โต๊ะทั้งหมด
What year did Bryant Heating enter?It is not neccessary to use all the tables.
 table_name_48:  (year [ INTEGER ] entrant [ VARCHAR) ]
SELECT SUM(year) FROM table_name_48 WHERE entrant = "bryant heating"