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

### Instruction:
If the number of barangays is 19, what is the population density?

### Inputs:
table_name: table, columns: ['City / Municipality', 'No. of Barangays', 'Area (km²)', 'Population (2010 Census)', 'Pop. density (per km²)']

### Response:
SELECT Pop. density (per km²) FROM table WHERE No. of Barangays = 19