Question

A peanut butter fudge recipe calls for 1 and 1/3 cups of sugar, ¾ cup of milk, 1 teaspoon of vanilla and ½ a
jar of peanut butter, how will the other ingredients in the recipe have to be altered if one ingredient is
altered as specified below in order for the fudge to turn out?
a) 1 cup of sugar
b) 2 cups of milk
c) 4 teaspoons of vanilla