Most Japanese envelope sizes are metricated traditional. sizes; Width precedes height; Metric measurements are the finished envelope. size; Inch measurements are approximate (calculated at 25.4 mm = 1 inch. and rounded off).
Labor unions represent the interests of the worker. In the theater industry, actors are the workers and the Actor's Equity Association is the union. Non-equity actors are not represented under the AEA and receive no membership benefits. Determining a general salary for non-equity actors is a challenging task.
Actors were semi-professional, at best. Three-actor rule (that only three actors were in productions) - seems supported by evidence, but questioned by some. Oedipus at Colonus - could have only three actors, but only if a different actor played the same character in different scenes.