Co-efficient of thermal expansion of glass is decreased by the addition of _______________ during its manufacture?

A. Low co-efficient of expansion
B. High co-efficient of expansion
C. High melting point
D. Both B. and (C)

A. Pain relievers
B. Antibiotics
C. Used in the treatment of T.B.
D. Used in the treatment of typhoid

A. Hydrogenation
B. Esterification
C. Saponification
D. None of these

A. 15
B. 35
C. 55
D. 70