Fibre boards can be

Asbestos . . . . . . . .

Stones used for the construction of retaining walls must be

To retard the initial setting time of cement, the compound responsible, is

Asphalt is obtained from

Which of the following is the purest form of iron?

Formula for quick lime, is

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

The commonly used color pigment in paints, is