Suppose a bicycle manufacturer that uses heijunka has received 1200 orders (400 units of model A, 200 units of model B, and 600 units of model C) during the first quarter of this year. Suppose the firm's plant operates 4 weeks a month and 5 days a week, producing 300 units of any model a week. Further suppose that the time required to produce one unit, regardless of model, is the same. Because the plant produces 300 units a week, the firm has decided to operate its plant during the entire month of April this year, so that it can exactly meet the actual demand (4 weeks * 300 units = 1200 units)