Evaluate the marginal cost of expanding Pfizer's vaccine distribution network.

Cost Components	Fixed Costs ($)	Variable Costs per Unit ($)	Production Volume (units)
Vaccine Distribution Network	4,500,000,000	1	2,000,000,000

Requirements:

Calculate the marginal cost per unit.

Determine the break-even point for the vaccine distribution network expansion.

Analyze how changes in production volume affect the marginal cost.

Provide recommendations for cost management in vaccine distribution.