Fly ash, accelerators, superplasticizers, and air entrainment are added to a concrete mix to:

a. increase its strength.
b. increase its resistance to cracking.
c. to alter its properties in different ways.
d. to increase the concrete’s abrasion resistance.
e. to reduce the amount of reinforcing steel required.

The answer is: A. increase your strength. B. increases its resistance to cracking. D. to increase the concrete’s abrasion resistance.

Explanation:

1.- The main use of Fly Ash, is characterized by being a magnificent product in the construction industry, contributing to the  formation of a cement material that adds strength, impermeability, and other characteristics to the resulting structure.

2.- Using fly ash and other products, they produce more compact concretes, therefore more impermeable and, as a consequence, less exposed to aggressions of external agents being therefore more durable.

3.- In addition to fly ash, it has been possible to manufacture cements for specific uses, such as concrete for dams.

The answer is: A. increase your strength. B. increases its resistance to cracking. D. to increase the concrete’s abrasion resistance.

for many centuries there were important factors which the economies of the muslim empires developed increasingly. they applied economic procedures in production, investment, finance, taxation and property. they used to tax certain goods (for example: harvest), they charged interest on money lent, they signed contracts with merchants; they relied on a common currency, and they used checks as well as promissory notes. with the money collected by means of taxation, the government provided the needy with an income. in addition, trading networks covered huge distances, so far regions started to have contact and exchange goods. this trade network covered areas of asia, africa and europe.