Use the following for questions 26. A researcher is investigating alertness. She asked 20 subjects who habitually had either 6, 7, 8, or 9 hours of sleep every night to complete the Stanford Sleepiness Scale (SSS). The SSS is a measure of alertness and simply requires the subject to rate his or her level of alertness by responding with a number between 1 (very alert) and 7 (struggling to stay awake). Each subject did this in the morning, the afternoon, the evening, and at night. The subject was also asked to self-identify as either a night person or a morning-person. It is safe to assume that none of the subjects have unusual hours, such as getting up at 10 at night. In the space below, please list the variables; please state how many categories each variable has (if more than six, simply write \"several\"); please list the categories (if there are more than six categmies, simply list six possible categories you may have to guess what the categories may be don't worry if you have the correct units that isn't part of the question); and please state the scale of measurement for each variable (i.e., nominal, ordinal, interval, ratio). Put each variable on a separate row