1. On September 1, S obliges himself to sell a specific horse to B if B passes the CPA examination. On November 1, S sold the horse to A. On November 18, B passed the CPA examination. Who has a better right to the horse? Explain your answer.

2. X obliges himself to deliver a specific car to Y on April 1, 2021. Y will pay 1,000,000 upon the delivery of the car. On April 1, X delivered the car but Y did not pay 1,000,000. What are the remedies available to X? May he choose fulfillment of the obligation after choosing rescission? Explain your answer.