Analyze cost behavior and cost structure for a technology firm.

Cost Category	Fixed Costs ($)	Variable Costs per Unit ($)	Sales Volume (Units)
Product Development	$500,000	-	-
Marketing and Sales	-	$50 per unit	10,000 units

Requirements:

Classify costs as fixed or variable based on the provided data.

Calculate the total fixed costs and variable costs for the given sales volume.

Discuss how changes in sales volume affect the cost structure and profitability.