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

### Instruction:
What is the rank 6 lowest win who's first win was at the 1950 British Grand Prix?

### Inputs:
table_name: table, columns: ['Rank', 'Engine', 'Wins', 'First win', 'Latest win']

### Response:
SELECT MIN Wins FROM table WHERE Rank > 6 AND First win = 1950 british grand prix