bank

Review the following transactions that take place between the same seller and buyer for the same item, in some cases for different periods and different prices. Earlier Period: a date earlier than the sale deferred payment date. Longer Period: a date later than the sale deferred payment date. 1. I sell for 120 deferred and repurchase for 120 cash 2. I sell for 120 deferred and repurchase for 120 deferred to earlier period 3. I sell for 120 deferred and repurchase for 120 deferred to same period 4. I sell for 120 deferred and repurchase for 120 deferred to longer period 5. I sell for 120 deferred and repurchase for 100 cash 6. I sell for 120 deferred and repurchase for 100 deferred to earlier period 7. I sell for 120 deferred and repurchase for 100 deferred to same period 8. I sell for 120 deferred and repurchase for 100 deferred to longer period 9. I sell for 120 deferred and repurchase for 140cash 10. I sell for 120 deferred and repurchase for 140 deferred to earlier period 11. I sell for 120 deferred and repurchase for 140 deferred to same period 12. I sell for 120 deferred and repurchase for 140 deferred to longer period Which of the above (if any) is Forbidden? Transactions no 4,5 and 9 are forbidden ones (as per AAOIFI)