Polymers are formed by suspension polymerization of monomers, including one or more styrenic monomers, in the presence of polymeric, emulsion based seeds. Representing a foundation from which all types of writing and its conventions may be explored, the manipulatives have been so designed to aid students in the process of recalling, interpreting, applying, analyzing, synthesizing andor judging during the writing process. Signals emitted from the base station and terminal devices are received and repeated by the receiving and transmitting antenna set. When the ink level is up to the window, light irradiated from the optical sensor permeates the window. The mass spectrometer is operated in a trapping mode to trap ions in the ion trap, and the ion trap is filled for the fill time, as just determined.