I am having difficulty calculating best/worst case scenarios.

I have calculated the relative numbers but I am stuck. I do not know how to proceed with calculations?

Base case Unit sales: 52,000

Price per unit $50

Variable costs per unit: $30

Fixed costs per year: $730,000

Initial cost: $1,080,000

Project life (years): 10

Required return: 15%

Tax rate: 35%