Final answer:
We cannot determine the exact number of cups of sugar needed without knowing the ratio.
Step-by-step explanation:
To find out how many cups of sugar are needed, we need to know the ratio of cups of sugar to cups of water. Unfortunately, the question does not provide this information. Therefore, we cannot determine the exact number of cups of sugar needed. However, if a specific ratio is given, we can use that to calculate the amount of sugar needed.