A hydraulic machine is being planned for acquisition at a cost of $5,000. During its useful life of 7 years, it is expected to generate a gross income of $3,400 per year.Its annual maintenance cost is projected to be $300. The cost of space to house the machine and of the utilities is $900 per year. Determine the payback period for the machine by considering the time value of money. Assume annual compounding with i = 10% per year.