Acoma, Incorporated, has determined a standard direct materials cost per unit of $8 ( 2 feet $4 per foot). Last month, Acoma purchased and used 4,200 feet of direct materials, for which it paid $15,750. The company produced and sold 2,000 units during the month. Required: Calculate the direct materials price, quantity, and spending variances. Note: Indicate the effect of each variance by selecting "F" for favorable, "U" for unfavorable, and "None" for no effect (i.e., zero variance)