Rehydrator makes a nutrition additive and expects to sell 3,000 units in January, 2,000 in February, 2,500 in March, 2,700 in April, and 2,900 in May. The required ending inventory is 20% of the next month’s sales, and the beginning inventory on January 1 was 600 units. Prepare a production budget for the first four months of the year.