A.Those which reflect heat
B.Those which absorb heat
C.Those which have melting point above 1950?C
D.Those do not malt in a normal furnace
E.Those which can be cast in the form of bricks
A.Those which reflect heat
B.Those which absorb heat
C.Those which have melting point above 1950?C
D.Those do not malt in a normal furnace
E.Those which can be cast in the form of bricks