Required rate of return is 12%, what level of annual cash savings?

Grouper's Lawn Service needs to purchase a new lawnmower costing $8,696 to replace an old lawnmower that cannot be repaired. The new lawnmower is expected to have a useful life of 4 years, with no salvage value at the end of that period. (a) If Grouper's required rate of return is 12%, what level of annual cash savings must the lawnmower generate to be considered an acceptable investment under the net present value method?