Bradley works as a traveling salesman and leases a car for his business. the leasing company has a base rate for the first 15,000 miles per year, but has an additional charge of $500 + $0.25/mile for each mile over the 15,000. bradley has already driven 4300 miles in the first three months. if he drives a similar amount for the rest of the year, how much will he have to pay extra? show all work and explain your answer.

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?