I know you can only answer the first four but if you could include the formulas for the other 2 I would appreciate it. Thanks

30. The labor rate variance for March is: A) $4,578 unfavorable. B) $1,470 unfavorable. C) $4,578 favorable. D) $1,470 favorable. QUESTIONS 28 THROUGH 33 ARE BASED ON THE FOLLOWING INFORMATION: Cox Engineering performs cement core tests in its laboratory. The following standards have been set for each core test performed: 31. The labor efficiency variance for March is: A) $480 favorable. B) $480 unfavorable. C) $192 favorable. D) $192 unfavorable. Direct materials, 3 pounds @ $0.75 per pound. Direct labor, 0.4 hours @ $12.00 per hour. Variable factory overhead, 0.4 hours @ $4.00 per hour. Fixed factory overhead, 0.4 hours @ $10.00 per hour. 32. The variable overhead rate variance for March is: A) $320 unfavorable. B) $320 favorable. C) $160 unfavorable. D) $160 favorable. Manufacturing overhead is assigned to core tests on the basis of direct labor hours. Budgeted fixed manufacturing overhead for the period was $8,000. The denominator activity used for determining the overhead rates was 2,000 core tests or 800 direct labor hours. On March 1 no direct materials (sand) were on hand. The following events occurred during March: 33. The variable overhead efficiency variance for March is: A) $320 unfavorable B) $320 favorable. C) $160 unfavorable. D) $160 favorable. 8,600 pounds of sand were purchased at a cost of $7,310. 7,200 pounds of sand were used for core tests. 840 actual direct labor hours were worked at a cost of $8,610. Actual variable manufacturing overhead incurred was $3,200. Actual fixed manufacturing overhead incurred was $8,100. The company actually performed 2,000 core tests during the month. 28. The materials price variance computed on the basis of the quantity purchased for March is: A) $860 unfavorable. B) $860 favorable. C) $281 unfavorable. D) $281 favorable. 29. The materials quantity (efficiency) variance for March is: A) $ 900 favorable. B) $1,950 favorable. C) $1,950 unfavorable. D) $ 900 unfavorable