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

### Instruction:
what is the value of the audio with a just ratio 21:20

### Inputs:
table_name: table, columns: ['interval name', 'size (steps)', 'size (cents)', 'just ratio', 'just (cents)', 'error', 'audio']

### Response:
SELECT audio FROM table WHERE just ratio = 21:20