20. In the facility with 220 lighting fixtures, the lighting is used for 3904 hours per year. For each fixture, Lamp A with a life time of 18156 hours and a replacement cost of $5.93 is to be replaced with lamp B with lifetime of 19825 hours and replacement cost of $11.25.Assuming continual lamp replacement i.e lamps are replaced as and when they fail, what is savings in replacement cost (in dollars) to 2 d.p