Caleb manufacturing produced 3,000 units during June even though the company had anticipated producing 2,800 units. The company's employees actually logged 3,200 hours during the month and were paid \($8.40\) per hour. The company's standard costing system indicates 1 direct labor hour per unit at a standard wage rate of \($8.70\). Which of the following is incorrect?

a. The labor rate variance is \($960\) favorable.

b. The labor efficiency variance is \($3,480\) unfavorable.

c. The labor efficiency variance is \($1,740\) unfavorable.

d. The actual amount paid to employees for their labor during the month is \($26,880.\)