1) What do you mean by plastics? prepare down the essential differences between thermoplastic, thermosetting and elastomer resins. describe with suitable exs. describe about various kinds of resins. describe the manufacture of phenol-formaldehyde resin with a neat and suitable flow diagram. describe the viscose process for manufacture of Rayon fiber indicating with the steps involved in detail. Compare natural and synthetic rubbers. Describe how natural rubber is prepared? prepare down its significant properties.