Vicat's apparatus is used to determine the

The timber whose thickness is less than 5 cm and the width exceeds 12 cm, is called a

Gypsum is added in the manufacture of Portland cement

The wood generally used for railway sleepers is

The strength of cement concrete is directly proportional to cement-water ratio.

The bricks should be burnt at temperature from

The rocks formed due to solidification of molten mass laying below or above the earth surface, are called

A first class brick should have a minimum crushing strength of

The rocks formed due to alteration of original structure under heat and excessive pressure are called metamorphic rocks.