The standards for product G78V specify 4.7 direct labor-hours per unit at $12.50 per direct labor-hour. Last month 1,660 units of product G78V were produced using 7,860 direct labor-hours at a total direct labor wage cost of $94,220. Required: a. What was the labor rate variance for the month? b. What was the labor efficiency variance for the month? (Indicate the effect of each variance by selecting "F" for favorable, " U " for unfavorable, and "None" for no effect (i.e., zero variance). Input all amounts as positive values.)