There are two processes in a manufacturing plant: printing and assembly. Each product is made up of three pieces: one unit of part 1 and two units of part 2. The parts are fabricated by a single printer that requires a set up time of 33 minutes switching between the two part types. Once the printer is set up, the activity time for parts, regardless of type, is 0.5 minutes for each piece. Currently, the printer rotates its production between one batch of 120 part 1's and 240 part 2's. At assembly, parts are assembled manually to form the finished products. The three parts and a number of small purchased components are required for each unit of final product. Each product requires 31 minutes of labor time to assemble. There are 20 workers in assembly. There is sufficient demand to sell every product the system can make. What batch size for the printer would minimize inventory but ensure the assembly process operates at maximum capacity