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).
Top Ivy League Schools: Harvard or Yale? Part of the USâs elite group of Ivy League schools, Harvard and Yale are among the worldâs most acclaimed, aspired-to and competitive universities. Of the eight Ivy League members, these are some of the two highest ranking in the QS World University RankingsÂ®. In the 2015/16 edition, Harvard is ranked 2nd in the world and Yale 15th.