The static budget for the month of May was for 3,000 units with direct materials at $28 per unit. Direct labor was budgeted at 30 minutes per unit for a total of $18,000. Actual output for the month was 3,000 units with $84,000 in direct materials and $19,300 in direct labor expense. The direct labor standard of 30 minutes was maintained throughout the month.

Determine whether a favorable or unfavorable variance occurred and what caused it.

please show explanation. Thank you