7-3. Bilateral versus Unilateral Contracts. William Greene began working for Grant Building, Inc., in 1959. Greene allegedly agreed to work at a pay rate below union scale in exchange for a promise that Grant would employ him "for life." In 1975, Oliver Realty, Inc., took over the management of Grant Building. Oliver Realty's president assured former Grant employees that existing employment contracts would be honored. During that same year, Greene explained the terms of his agreement to an Oliver Realty supervisor. The supervisor stated that he would look into the matter but never got back to Greene. After twenty-four years of service, Greene was fired by the new owners of the business. Greene sued Oliver Realty for breach of a unilateral contract. Discuss fully whether Greene and Oliver Realty had a unilateral contract. [Greene v. Oliver Realty, Inc., 363 Pa.Super. 534, 526 A.2d 792 (1987)]