Question: Who was the American vocalist, guitarist, and bandmate of Tony Rombola, who is ranked in the top 50 of the top 100 Heavy Metal Vocalists by "Hit Parader"
{'answer': 'Sully Erna', 'supporting_facts': [['Tony Rombola', 0], ['Tony Rombola', 2], ['Sully Erna', 0], ['Sully Erna', 2]]}