Sage Corporation uses a standard cost system to account for the costs of its one product. Standards are 3.00 pounds of materials at $14.0 per pound and 4.0 hours of labor at a standard wage rate of $12.00. During July, Sage Corporation produced 3,300 units. Materials purchased and used totaled 10,750 pounds at a total cost of $143,950. Payroll totaled $156,546 for 13,380 hours worked. Required: a. Calculate the direct labor rate variance. Note: Do not round your intermediate calculations. Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (i.e., zero variance). b. Calculate the direct labor efficiency variance. Note: Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (i.e., zero variance). c. Calculate the direct labor spending variance. Note: Indicate the effect of variance by selecting "Favorable", "Unfavorable", or "None" for no effect (i.e., zero variance)