12- An industrial manufacturing plant installs a new filtration system at a cost of $15,000. The system is expected to last 10 years and have a $1,000 salvage value at the end of its life. The annual maintenance cost starts at $3,000 and increases by 8% annually. i. Determine the present worth of the installation and maintenance costs, assuming a discount rate of 7% per year. ii. If the plant decides to replace the system after 5 years, what is the equivalent present worth of the remaining cost obligations at the end of year 5?