So, if they charge 5% for non-food items, the result should be, because 3.00$ for the lightbulb, 2.50*5/100 = 0.125 + 2.50 = 2.625$ for the cereal, and 50*5/100 = 0.025 + 0.5 = 0.525, which gives us a total of 6.15$! Hope this helps, brainliest is always appreciated.