Anew episode of charlie's favorite tv series will be aired 25 minutes after charlie gets home from school. which method should charlie use to most accurately determine when 25 minutes have passed?

charlies should look at a clock that shows hours and minutes only.

charlie should count the minutes in his head after he gets home from school.

charlie should use an hourglass and flip it over every time the sand runs out.

charlie should use a stopwatch with minutes and seconds.

Stu and ambrose are working together on a study of whether diet is related to students' mental health. first, they randomly select 10 students from the student center and 10 students from the office of counseling and psychological services. then, they ask students to rate their diet in terms of healthiness on a scale of 1-100 before completing a 20-item mental health survey. a) name one of the constructs being studied b) how was the construct you named above operationally defined in this experiment? e) was the variable you described above their independent variable, their dependent variable, or a controlled variable? d) what is a confounding variable? what is a potential confound in this study?