On Monday, Khalid said to Rizwan, ‘I will sell you my boat for Rs.20,000·00 if it rains before 1.00 pm on Friday’. Rizwan agreed and paid Rs.10,000·00 in advance. On Friday afternoon, rainfall started at 1.15 pm. Rizwan is ready to pay the remaining Rs.10,000·00 to buy the boat, but Khalid is not willing to deliver the boat.Required:In relation to the law of contract, advise Khalid and Rizwan as to their mutual rights and obligations. (10 marks)