Which of the following sedimentary rocks changes into quartzite by metamorphic action?

The variety of pig iron used for manufacture of wrought iron, is

Pick up the correct statement from the following:

The rock generally used for roofing, is

For the manufacture of Portland cement, the proportions of raw materials used, are

Kaolin is chemically classified as

Vanadium steel is generally used for

Pick up the correct statement from the following:

A good quality stone absorbs water less than