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

### Instruction:
Which Enrollment has a Primary Conference of mid-hoosier, and a County of 16 decatur, and an IHSAA Class of aa?

### Inputs:
table_name: table, columns: ['School', 'Location', 'Mascot', 'Enrollment', 'IHSAA Class', 'County', 'Primary Conference']

### Response:
SELECT Enrollment FROM table WHERE Primary Conference = mid-hoosier AND County = 16 decatur AND IHSAA Class = aa