Please solve by hand and show what equation is used, thanks

7. ACME Inc. manufactures jet packs. Maintenance of their current manufacturing equipment costs $8,000 per year. (a) If interest is 5% per year, what is the equivalent present worth of ten years of maintenance? (b) ACME can purchase a ten-year maintenance agreement for $55,000 paid now. This agreement would cover all maintenance costs for the ten years. Should they purchase the agreement? Why or why not