Mrs. Bajracharya's house has 15A electricity meter. She uses 5 LED bulbs of 10 watt each for 4 hours, 2 televisions of 60 watt each for 5 hours and a refrigerator of 250
watt for 2 hours everyday. Find the cost of payment of the bill of a month at the rate
of Rs 4 per unit up to 20 units, Rs 7 per unit from 21 to 30 units and Rs 8.50 from 31
to 50 units with Rs 100 service charge, if the payment is made on 35th day of meter
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Your vet has placed your pet on a diet. the diet is to contain at least 12 mg of fat and at least 14 mg of protein per serving. these requirements are to be obtained from two food sources. source a contains 2 mg of fat and 2 mg of protein per serving. source b contains 1 mg of fat and 3 mg of protein per serving. if source a sells for $1.28 per serving and source b sells for $1.12 per serving, how many servings of each type should be purchased to satisfy the requirements at minimal cost?