According to the U.S. Census Bureau, the county has a total area of 685 square miles (1,770 km2), of which 681 square miles (1,760 km2) is land and 3.8 square miles (9.8 km2) (0.6%) is water. It is the fourth-largest county in Tennessee by area. The county is located atop the Cumberland Plateau.
Revenue passenger kilometres (RPK) is a measure of the volume of passengers carried by an airline. A revenue passenger-kilometre is flown when a revenue passenger is carried one kilometre. A passenger for whose transportation an air carrier receives commercial remuneration is called a revenue passenger.
Rho-associated protein kinase (ROCK) is a kinase belonging to the AGC (PKA/ PKG/PKC) family of serine-threonine kinases.he kinase activity is switched on when Rho-GTP binds to the Rho-binding domain of ROCK, disrupting the autoinhibitory interaction within ROCK, which liberates the kinase domain because ROCK is then no longer intramolecularly folded. Other regulators. It has also been shown that Rho is not the only activator of ROCK.