Vaughn Industries has adopted the following production budget for the first 4 months of 2022. Month Units Month Units January 8,000 March 4,000 February 6,400 April 3,200 Each unit requires 2 pounds of raw materials costing $3 per pound. On December 31, 2021, the ending raw materials inventory was 3,200 pounds. Management wants to have a raw materials inventory at the end of the month equal to 20% of next month's production requirements. Prepare a direct materials purchases budget by month for the first quarter.