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

### Instruction:
What is the frequency of the station that was launched on 21 August 1994?

### Inputs:
table_name: table, columns: ['Call sign', 'Launched', 'Transmitting from', 'Coverage', 'Languages', 'Frequency']

### Response:
SELECT Frequency FROM table WHERE Launched = 21 august 1994