1.In a contract containing an option period, when is the offerer not allowed to withdraw his offer even before acceptance by the offeree? When is the offerer allowed to withdraw his offer even after acceptance?

2. L and M entered into a contract with Y. L's consent was obtained only because M had deceived or defrauded him. May L ask for annulment of the contract with Y?

3. When his father died, but before delivery of the property to him, a son sold his share of the property inherited. Is the sale valid?

4. A guardian of W sold W's mansion worth P50 million for P25 million. May the contract be rescinded on the ground of lesion?

5. S sold to B a specific car for P800,000. B was unable to pay for it. Has S the right to have the sale decalred void by the court on the ground of absence of cause for non-payment of the price?