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

### Instruction:
What is Launched, when Laid Down is "31 October 1981"?

### Inputs:
table_name: table, columns: ['Ship', 'Hull Number', 'Laid down', 'Launched', 'Commissioned']

### Response:
SELECT Launched FROM table WHERE Laid down = 31 october 1981