It follows from this definition that every set is disjoint from the empty set, and that the empty set is the only set that is disjoint from itself. A family F of sets is pairwise disjoint if, for every two sets in the family, their intersection is empty.
Ozark County Land Info. Ozark County is a county in Missouri. It covers 755 square miles (483,283 acres), which represents less than one percent of the state total. Of Missouri's 115 counties, Ozark County ranks 91st in terms of the size of its population (9,409, according to 2015 Census estimates).
Located in the south-central United States, the Ozarks are a heavily forested group of highlands. They extend southwestward from St. Louis, Missouri, to the Arkansas River. Along with the adjacent Ouachita Mountains, they represent the largest area of rugged topography between the Appalachians and the Rockies.