Below is an instruction that describes a task. Write a response that appropriately completes the request.

### 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?

### Inputs:
table_name: table, columns: ['Year', "Men's Open", "Women's Open", 'Mixed Open', "Men's u20", "Women's u20", 'Senior Mixed', "Men's 30", "Women's 30", "Men's 35", "Women's 35", "Men's 40", "Women's 40", "Men's 45", "Men's 50"]

### Response:
SELECT Men's 50 FROM table 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