Concrete is a mixture of cement, water, sand, gravel, crushed rock, or other aggregates. Sometimes, one or more admixtures are added to change certain characteristics of the concrete, such as workability, durability, and time of hardening.
Top 100 Colleges by Highest Tuition. Here are the top 100 most expensive colleges by tuition for the 2008-2009 school year. The latest numbers can be found in our most expensive colleges ranking. Notes: Some colleges like Bates College, Colby College, Middlebury College, and Union College have a comprehensive fee (tuition + room/board).
In 2013, the five postsecondary institutions with the highest enrollment were University of Phoenix, Online Campus, with 212,000 students; Ivy Tech Community College, with 98,800 students; Liberty University, with 77,300 students; Miami Dade College, with 66,300 students; and Lone Star College System, with 64,100 students.