QRS Ltd. manufactures electronics and incurred the following costs for the production of 10,000 units:

• Actual direct materials cost: $28,000
• Standard direct materials cost: $22,000
• Actual direct labor cost: $20,000
• Standard direct labor cost: $18,000

Calculate the following variances:

1. Direct materials price variance.
2. Direct materials quantity variance.
3. Direct labor rate variance.
4. Direct labor efficiency variance.