Dennis is a dentist who has registered for GST. During the current tax year, his total receipts from dental services he supplied equalled $44,000.

Dennis paid for the following expenses during the current tax year:

practice rent of $6,600;

electricity and gas of $2,200;

liability insurance costs of $3,300 and

staff salaries of $411,000.

Required: Calculate the net GST payable to or refundable from ATO. Support your answer with reference to relevant Australian Goods and Services Tax legislation.