With reference to 'fly ash' produced by the power plants using coal as fuel, which of following are correct?1.fly ash can be used in the production of bricks for building constructions.2. fly ash can be used as a replacement for some of the portlands cement content of concrete.3.fly ash is made up of silicon di oxide and calcium oxide only and doesnot contain any toxic elements.select correct answer?

With reference to 'fly ash' produced by the power plants using coal as

1.	With reference to 'fly ash' produced by the power plants using coal as fuel, which of following are correct?1.fly ash can be used in the production of bricks for building constructions.2. fly ash can be used as a replacement for some of the portlands cement content of concrete.3.fly ash is made up of silicon di oxide and calcium oxide only and doesnot contain any toxic elements.select correct answer?
A.	1,2
B.	2
C.	1,3
D.	3
Answer» B. 2