Calculus Company makes professional calculators. The profit plan and actual results for the previous year, 2019, are as follows:

Profit Plan

Actual Results

Volume

Pounds

Volume

Pounds

Sales

6,000

36,000

7,000

49,000

Cost of Goods Sold

Raw material (KG)

3,000

18,000

1,000

15,000

Raw material (L)

1,200

7,200

650

19,500

Labor (Hours)

300

3,600

280

5,600

Contribution Margin

7,200

8,900

Other costs

Energy

1,000

1,900

Maintenance

750

600

Depreciation

1,400

1,600

Profit before interest and tax

4,050

4,800

The plant manager, Maher, has instructed the plant management accountant to prepare a detailed report to be sent to corporate headquarters comparing each component's actual result with the amounts set forth above in the annual budget.

Required:Explain the difference between the expected and actual profit. Show your workings.