Pick up the correct statement from the following:
(A) Plastics have generally low melting point
(B) The coefficient of thermal expansion of plastics is about three times than that of steel
(C) The acoustical boards prepared by impregnating fibre-glass with phenolic resins has
absorption coefficient of about 0.67
(D) All the above
(A) Plastics have generally low melting point
(B) The coefficient of thermal expansion of plastics is about three times than that of steel
(C) The acoustical boards prepared by impregnating fibre-glass with phenolic resins has
absorption coefficient of about 0.67
(D) All the above