- **G1 – Total sales:** $110,000
- **1A – GST on sales:** $110,000 ÷ 11 = **$10,000**
- **1B – GST on purchases:** $66,000 ÷ 11 = **$6,000**
- **W2 – PAYG withholding:** $40,000 × 20% = **$8,000**
- **Net amount payable:** ($10,000 − $6,000) + $8,000 = **$12,000**