Jason owns Property A and Property B. Jason's neighbor, Heather would like to purchase Jason's property A. Heather tried to manipulate Jason (as he was old) to sell Property A at RM500,000 although the market value for Property A was RM1,000,000. Jason did not respond as he was distracted at that time. When Heather asked Jason again when she visited him, Jason agreed to sell Property A at RM500,000 as he was under the impression that Property B was sold to Heather instead of Property A.Explain the validity of contract between Jason and Heather for Property A to the concept of offer and acceptance.