The phone lines to an airline ticket reservation system are occupied 40% of the time. assume that the events that the lines are occupied on successive calls are independent. (a) if 10 calls are placed, what is the probability that the lines are occupied for exactly 3 calls? (b) if 10 calls are placed, what is the probability that for at least 1 call the lines are not occupied? (c) a person makes 10 calls per day for 365 days in a row. for how many of those days do you expect that all 10 calls got through (i. e., that the lines were not busy for a single call)?

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.