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

### Instruction:
Tell me the sum of rank for australia when points are less than 79

### Inputs:
table_name: table, columns: ['Rank', 'Previous Rank', 'Name', 'Nationality', 'Team', 'Points']

### Response:
SELECT SUM Rank FROM table WHERE Nationality = australia AND Points < 79