Since the beginning of the millennium, the united states has witnessed closure of many internet start-up companies. according to the model of perfect competition, these companies must have shut down in the short run because:

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.

Ryngard corp's sales last year were $38,000, and its total assets were $16,000. what was its total assets turnover ratio (tato)? a. 2.04b. 2.14c. 2.26d. 2.38e. 2.49

Petra contracted to paint bret’s house for $2,000. after beginning the job, petra realizes that the house is really quite big, and she’s not going to make enough profit, so she tells bret she wants another $500 to finish the job. bret doesn’t want to pay more, but he’s afraid that if she walks off the job, he’ll have trouble finding someone else to finish it, so he agrees. is bret legally obligated to pay the extra $500?