Pig iron is manufactured from the ores by

The percentage of alumina in a good brick earth lies between

Jhumb bricks are

The compound of Portland cement which reacts immediately with water and also sets first is

Which of the following is a mineral?

Asbestos is

In stone masonry, stones (stratified rocks) are so placed that the direction of pressure to the plane of bedding is

Refractory bricks resist

Cast iron . . . . . . . .