A turtle and a snail start moving towards each other when they are 200 feet apart. The turtle is running at a speed of T feet per minute, and the snail is moving at a speed of S feet per minute.
a
How fast are they approaching each other?

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?