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

### Instruction:
What day did episode number 4 air originally?

### Inputs:
table_name: table, columns: ['№', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (million)']

### Response:
SELECT Original air date FROM table WHERE № = 4