Suppose that the observational units in a study are the patients arriving at an emergency room in a given day. For each of the following , indicate whether it can legitimately be considered a variable or not. If it is a variable, classify it as categorical ( and if it is binary) or quantitative. If it is not a variable, explain why not. a. Blood type b . Waiting time c . Mode of arrival (ambulance , personal car, on foot, other) d . Whether or not men have to wait longer than women e . Number of patients who artive before noon f . Whether or not the patient is insured g . Number of stitches required h . Whether or not stitches are required i . Which patients require stitches j . Number of patients who are insured k . Assigned room number