In a minimum of 300 words discuss the basic ingredients of concrete and their role in concrete properties (density, workability, strength, etc.) What is concrete reinforcement? What are the common types of reinforcing? Why steel is known as ideal material for concrete reinforcing? Discuss the characteristics of concrete construction for very tall buildings. In minimum of 300 words compare sitecast and precast concrete framing systems. Specify the advantages and disadvantages of each method.