State which of the following meets the definition of revenue under AASB 15/IFRS 15 for Toys2U Ltd, a retailer of toys. Give reasons for your answer.

1. Sales tax collected on behalf of the taxing authority

2. Gain on the sale of an investment property

3. Amounts receivable from customers who have purchased toys

4. Gain on the sale of equity securities held as investments

5. Revaluation increase on the revaluation of operating properties under AASB 116/IAS 1