What are the trands in physical properties

Dr. dow jones wants to know whether a problem-based approach to teaching economics will result in higher academic performance than his traditional method. of the six sections of economics 101 at his university, dr. jones randomly assigns three sections to the traditional method and three sections to the problem-based method for unit 1 of the course. then all sections switch the instructional method for unit 2. he plans to compare the performance of the two groups of sections on their unit 1 and unit 2 exams. this study employs a design.

To : of $25 up to 35 2 35 up to 45 5 45 up to 55 7 55 up to 65 20 65 up to 75 16 is$25 up to $35 ?

Atennis club charges a monthly membership fee of $150 and charges it members $10 per hour to use a court. there's also $500 fee to become a member. stella joined the tennis club last spring, and she has been a member for 5 months. she has been playing 10 hours of tennis each month. stella values an hour of her time at $20. during a boring afternoon meeting, stella thinks about reserving a court to work on her serve for an hour tonight. what's stella's opportunity cost of working on her serve for an hour?