The standard number of hours that should have been worked for the output attained is 8,000 direct labor hours and the actual number of direct labor hours worked was 8,400. If the direct labor price variance was $4,200 unfavorable, and the standard rate of pay was $9 per direct labor hour, what was the actual rate of pay for direct labor? a. $8.50 per direct labor hour b. $7.50 per direct labor hour 0. $9.50 per direct labor hour d. $9.00 per direct labor hour