Ollie owned a large tract of land known as Peterhill. During Ollie's lifetime, Ollie conveyed the easterly half (East Peterhill), situated in the municipality of Hawthorn, to Abel, and the westerly half (West Peterhill), situated in the municipality of Sycamore, to Betty. Each of the conveyances, which were promptly and properly recorded, contained the following language: The parties agree for themselves and their heirs and assigns that the premises herein conveyed shall be used only for residential purposes; that each lot created within the premises herein conveyed shall contain not less than five acres; and that each lot shall have not more than one single-family dwelling. This agreement shall bind all successor owners of all or any portion of Peterhill and any owner of any part of Peterhill may enforce this covenant. After Ollie's death, Abel desired to build houses on one-half acre lots in the East Peterhill tract as authorized by current applicable zoning and building codes in Hawthorn. The area surrounding East Peterhill in Hawthorn was developed as a residential community with homes built on one-half acre lots. West Peterhill was in a residential area covered by the Sycamore zoning code, which allowed residential development only on five-acre tracts of land. In an appropriate action brought by Betty to enjoin Abel's proposed construction on onehalf acre lots, the court will find the quoted restriction to be 
invalid, because of the change of circumstance in the neighborhood.  invalid, because it conflicts with the applicable zoning code.  valid, but only so long as the original grantees from Ollie own their respective tracts of Peterhill.  valid, because the provision imposed an equitable servitude. 