I have a hard time figuring out this problem. Can you please explain to me how to calculate this? Thank you for your help in advance!

Ira's Industrial Systems Company (ISC) is trying to decide between two different conveyor belt systems. System A costs $427,000, has a 6-year life, and requires $115,000 in pretax annual operating costs. System B costs $502,000, has an 8-year life, and requires $79,000 in pretax annual operating costs. Both systems are to be depreciated straight-line to zero over their lives and will have a zero salvage value. The tax rate is 33 percent and the discount rate is 24 percent. Which system should the firm choose? Why