Amath teacher is trying to analyze her test grades. she surveys the students to find out how many minutes they studied. she then makes a scatterplot of time studying and test grades. what is the domain? a) the students' grades on their tests b) the number of students in the class c) the different courses the teacher teaches d) the number of minutes the students studied

The answer is    d)  the number of minutes the students studiedin this case, the number of minutes would be the independent variable; the test grades would be the dependent variable that depends on the number of minutes the student studies. the independent variable is associated with the domain for a function. (the grades, in this case, would be the range.)it's more intuitive to have test scores as a function of time studied rather than time studied as a function of test scores, because you get good test scores from studying. your test scores depend on the amount of time studied.the number of students and different courses are irrelevant to this question.