The answer to this question would be: 0.375 cups of milk
In this question, you are asked how many cups of milk is 3/4 serving from 1/2 cup of milk. To answer this, you need to multiply the number of serving with the serving size.
If one serving is 1/2 cups of milk, then 3/4 servings would be:
3/4 servings * (0.5 cups / serving)= 3/8 cups of milk = 0.375 cups of milk