1. A owes B P100,000, secured by a real estate mortgage. On due date, X without the knowledge and consent of A paid B the whole indebtedness, which B accepted.

a. Is the obligation of A to B extinguished?

b. Can X compel B to assign or transfer to him the right in the mortgage?

c. Can X recover from A? How much?

2. A binds himself to repair the house of B. Before he can perform the obligation, the house was destroyed by an accidental fire. What is the effect? Explain.

3. In payment of his obligation, X gave Y a check which the latter accepted. Is the obligation extinguished? Explain.

4. If the creditor had repeatedly refused to accept payment without valid reason, is the obligation considered extinguished?

5. If the debtor dies without paying his indebtedness, is the obligation extinguished? What is the creditor dies before due date of payment, what is the effect?

6. A, 18 years old, borrowed P2,000 from B , 16 years old. On due date, A paid B and the latter lost the money in a gambling game. Is the payment made by A valid? Explain.

7. X, Y and Z owe a jointly P3,000. Subsequently, A donates to X his credit against the latter. Are Y and Z still liable to A?

8. X owes Y P2,000 payable on July 31, 2020. Y binds himself to deliver X one sack of rice worth P2,000 on July 31, 2020. Will compensation take place?

9. A owes B P500,000 payable after one year. One week after from date of contract. A and B agree to secure the obligation by a real estate mortgage (sangla ng lupain). Is there a novation? Explain.

10. A offers to sell his one and only motorcycle for P15,000 and B agrees to buy it for said amount. Is the contract perfected. Explain.

11. Suppose in the above problem, B wants to buy the motorcycle for P12,000. What is the effect.

12. On November 15, 2020, A sold to B his one and only car for P200,000 to be delivered and paid on November 30, 2020. Is there a perfected contract between A and B? When is the contract perfected?

13. X asked Y if he can borrow his car next week and the former agreed. Is the contact perfected between X and Y? Explain.

14. A offers to sell his car to B for P200,000. B tells A that he is buying it for P150,000. Is there a contract between A and B? Explain.

15. A offers to sell B his old laptop for P5,000 and gives B three days to decide whether to buy or not. The next day a sold the laptop to W without informing B. Is A liable for damages? Explain.

16. On March 1, 2020, A offered to sell his only car to B for P200,000. B accepted the offer by making his letter of acceptance on March 10, 2020. On March 7, 2020, A sold his car to X. On March 15, 2020, A received and read the letter of acceptance. Who has a better right over the car, B or X? Explain?

17. A sold to B ten bottles of brandy. A delivered the bottles of brandy but two of them were filled with black tea. Can B sue for annulment of the contract with damages? Explain.

18. X owes huge amount of money to several creditors. To make his property beyond the reach of his creditors, he executed a fictitious sale of his property. What kind of simulation of contract is this? What is the effect?

19. In what form my a contract appear? State the general rule and exceptions.

20. G, guardian of M, sold the latter's parcel of land worth P100,000 for only P90,000. Is the contract rescissible? Explain

21. X orally sold his lot to Y for P500,000 and the latter gave an earnest money in the amount of P50,000 which the former acknowledge in a receipt. Later on, X refused to comply with the contract. Can Y enforce the contract against X? Explain.

22. On December 1, 2020, A entered into a contract whereby B sold his one year production of eggs in his poultry farm for P50,000. Is the object valid?

23. X and Y entered into a contract dor smuggling or importation of contraband. What is the status of the contract? Do they have action against each other if one of them does not comply with the contract? What are the effects?

24. The President declared a state of emergency due to Covid-19 pandemic and the prices of basic commodities are fixed by the government. Suppose you bought kilos of rice and paid an amount beyond that which is fixed by the government, can you recover the excess amount that you paid with the legal interest?