Leaders of the state's six biggest public university systems are asking Texas leaders for nearly a billion-dollars to support higher education. In exchange, university chancellors promise not to raise undergraduate tuition for the next two years. Last month the chancellors sent a letter to Lt. Gov. Dan Patrick and other state leaders making the proposal. The letter was signed by the chancellors of the UT System, the Texas A&M System, the University of Houston System, the University of North Texas System, the Texas Tech System, and the Texas State University System.