Part a: a mechanic buys 2 barrels of oil. if there are 31.5 gallons in every barrel and approximately 3.785 liters for every gallon, approximately how many liters of oil did the mechanic buy? part b: the mechanic plans to pour the oil into 2–liter containers. how many containers will the mechanic need to hold all of the oil? explain your answer.

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?