This information is for the first two questions. A researcher was interested in the effect of exercise on academic performance in elementary school children.She went to the recess area of an elementary school and identified how active each student was.Those who were exercising vigorously received a five.As exercise decreased, the student was given a lower number until those who were sedentary received a one.She then compared the letter grades (in math) of the various groups of students with each other.The researcher also noted the student's gender and the number of friends the student played with during recess.

What is the scale of measurement of the variable "Level of Activity?"