QRS Ltd produces and sells a single product. The following information is available for the year ended 31 December 2024:

Selling price per unit: $50

Variable cost per unit: $30

Total fixed costs: $200,000

Required: a. Calculate the break-even point in units and dollars. b. Determine the margin of safety in units and dollars if the company expects to sell 12,000 units. c. Calculate the operating income if 12,000 units are sold. d. Explain the impact of a 10% increase in fixed costs on the break-even point and margin of safety.