Moss Company has prepared a sales budget of 45,000 finished units for a three-month period. The company has an inventory of 16,000 units of finished goods on hand at December 31 and has a target finished goods inventory of 18,000 units at the end of the succeeding quarter. It takes three gallons of direct materials to make one unit of finished product. The company has an inventory of 60,000 gallons of direct materials at December 31 and has a target inventory of 50,000 gallons at the end of the succeeding quarter. How many gallons of direct materials should be purchased during the three months ending March 31?