Suppose you currently have 7, 60 Watt, incandescent light bulbs which are on for 4.4 hours a night, every night (365 nights). If electricity costs 11.2 cents per kilowatt-hour, theoretically what wattage LED bulbs are needed if you were to place all your incandescent bulbs (keeping them on the same amount of time) to save $37 per year on the cost of running light bulbs?