To answer this question let's remember the definitions of qualitative and quantitative data:
• Qualitative data is data that describes the attributes or properties of what we are studying.
,• Quantitative data that describes certain quantity or amount. It is usually express by numbers with some unit associated it with it and it can be discrete or continuous. Discrete data is described by particular numbers in a range and continuos data is described by any number in any range.
With this in mind we conclude that Janelle is measuring qualitative data, since she is measuring the amount of water the student takes, furthermore this is continuous data since each student can drink any amount of water, that is, we can even divide the ounces in any decimal.