VARIABLE COSTING- SALES EXCEED PRODUCTION

Please help me UNDERSTAND how to work this problem.

The beginning inventory is 9,600 units. All of the units that were manufactured during the period and 9,600 units of the beginning inventory were sold. The beginning inventory fixed manufacturing costs are $21 per unit, and variable manufacturing costs are $60 per unit.

a. Determine whether variable costing income from operations is less than or greater than absorption costing income from operations.

b. Determine the difference in variable costing and absorption costing income from operations.