ANSWER and EXPLAIN

1. A will give B a bicycle. When is the obligation demandable?
2. A will give B P5,000 if the latter passes his Law 1 subject this semester. When is the obligation demandable?
3. A will give B P5,000 provided that if B fails his Law 1 subject this semester he shall return the amount to A. When is the obligation demandable?
4. I will pay you when my means permit me to do so. Is the obligation conditional?
5. X will give Y P50,000 if Y will kill W. What is the effect of the condition (on the obligation)?
6. A will give B P10,000 if A decides to sell his house. What is the effect of the condition?
7. X agrees to give his car to Y if Y passes the medical board examination. Before the result is release the house is totally destroyed by accidental fire and subsequently Y is one of the successful examinees. What is the effect?