N-methylcarbamate insecticide residues, including carbamate metabolites, are extracted with methanol. The extract is cleaned up by partitioning and column chromatography on a charcoal/Celite column. Residues are selectively determined
Production — Games 1 Monopolistic Competition Monopolistic competition arises when there are a large number of price-setting firms in an industry with free entry. Suppose there are n firms. In the short run, each firm faces an nth of the market demand curve