Direct Labor Variances Assume that Nortel manufactures specialty electronic circuitry through a unique photoelectronic process. One of the primary products, Model ZX40, has a standard labor time of 0.5 hour and a standard labor rate of $15.50 per hour. During February, the following activities pertaining to direct labor for Z40 were recorded: (a) Determine the labor rate variance. (b) Determine the labor efficiency variance. (c) Determine the total flexible budget labor cost variance