I need help with this exercise:

Grey is considering the replacement of some machinery that has zero book value and a current market value of $2,800. One possible alternative is to invest in new machinery that costs $30,000. The new equipment has a four-year service life and an estimated salvage value of $3,500, will produce annual cash operating savings of $9,400, and will require a $2,200 overhaul in year 3. The company uses straight-line depreciation. Required: Prepare a net-present-value analysis of Grey's replacement decision, assuming an 8% hurdle rate and no income taxes. Should the machinery be acquired? Note: Round calculations to the nearest dollar.