Furson Corporation makes a single product. In a recent period 6,540 units were made and there was an unfavorable labor efficiency variance of $26,500. Direct labor workers were paid $5 per hour and total wages were $190,000. The labor rate variance was zero. The standard labor-hours per unit of output is closest to:
a. 3.0
b. 3.2
c. 2.5
d. 5.0