I need help with direct labor efficiency variance calculation

Hunter Family Instruments makes cellos. During the past year, the company made 3,500 cellos even though the budget planned for only 3,600. The company paid its workers an average of $20 per hour, which was $0.50 higher than the standard labor rate. The production manager budgets 6 direct labor hours per cello. During the year, a total of 20,840 direct labor hours were worked. (a) Calculate the direct labor rate and efficiency variances. (if variance is zero, select "Not Applicable" and enter O for the amounts.) Direct labor rate variance Direct labor efficiency variance $