Interpretation of Pulmonary Function Tests

This is what level of measurement? 6.) The total knowledge score could range from 0 to 33. What level of measurement is the total knowledge score? 7.) Look at Table 1. What was the cumulative percent of students who were fourteen years old or younger? 8.) Look at Table 1. What level of measurement are age, sex, ethnicity and sexually active? 9.) ................
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