Martinez Industries has adopted the following production budget for the first 4 months of 2017. Month Units Month Units January 10,130 March 5,250 February 8,110 April 4,260 Each unit requires 5 pounds of raw materials costing $4 per pound. On December 31, 2016, the ending raw materials inventory was 9,110 pounds. Management wants to have a raw materials inventory at the end of the month equal to 20% of next months production requirements. Prepare a direct materials purchases budget by month for the first quarter.