instruction: Which Men's 50 has a Senior Mixed of n/A, and a Men's Open of gold coast sharks def sydney mets, and a Men's 30 of sydney mets def sydney scorpions, and a Women's u20 of southern suns def brisbane city cobras?
response: SELECT "Men's 50" FROM table_46941 WHERE "Senior Mixed" = 'n/a' AND "Men's Open" = 'gold coast sharks def sydney mets' AND "Men's 30" = 'sydney mets def sydney scorpions' AND "Women's u20" = 'southern suns def brisbane city cobras'