Recall the setup from the previous HW. There are n cars on a one-way circular track. Among all of them, they have exactly enough fuel (in total) for one car to exactly circle the track. Each car burns CS 70, Spring 2020, HW 2 3 exactly the same amount of fuel per unit of distance. Two cars at the same location may transfer fuel between them. (a) Prove that there exists one car that can circle the track, by gathering fuel from other cars along the way. (That is, one car moving and all others stopped). Hint: Use induction and the previous part of this problem from HW1.

In a study of the relationship between socio-economic class and unethical behavior, 129 university of california undergraduates at berkeley were asked to identify themselves as having low or high social-class by comparing themselves to others with the most (least) money, most (least) education, and most (least) respected jobs. they were also presented with a jar of individually wrapped candies and informed that the candies were for children in a nearby laboratory, but that they could take some if they wanted. after completing some unrelated tasks, participants reported the number of candies they had taken. it was found that those who were identiď¬ed as upper-class took more candy than others. in this study, identify: (a) the cases, (b) the variables and their types, (c) the main research question, (d) identify the population of interest and the sample in this study, and (e) comment on whether or not the results of the study can be generalized to the population, and if the ď¬ndings of the study can be used to establish causal relationships.