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

### Instruction:
What date was the circuit, snetterton, when riki christodoulou had the fastest lap?

### Inputs:
table_name: table, columns: ['Circuit', 'Date', 'Pole Position', 'Fastest Lap', 'Winning driver', 'Winning team']

### Response:
SELECT Date FROM table WHERE Circuit = snetterton AND Fastest Lap = riki christodoulou