30 If one were to repeatedly sample from the population and construct many, many confidence intervals, how does the confidence level of each confidence interval constructed relate to the simulated result? VOTE (not part of question): Remember to rip up your scrap paper on camera before submitting the exam. O a. The confidence level will be percentage of all the sample proportions that fall in the first constructed confidence interval. ) b. The confidence level will be the percentage of standard errors away from the sample proportion one needs to go to be that percentage confident in the interval capturing the population proportion. c. The confidence level will be the probability that the sample proportion will be the same as the population proportion d. The confidence level will be the approximate percentage of those confidence intervals constructed that capture the unknown population proportion. 28 With the increased use of credit cards, debit cards, and other electronic methods of payment, will the United States eventually stop using cash? In a July 2016 Gallup poll of a random sample of 1,024 American adults, 635 of them thought the United States would become a cashless society in their lifetimes. An approximate 95% confidence interval for this situation is (0,59 0.65). Which of the following statements is the best interpretation of this confidence interval? O a. We are 95% confident that the interval (0.59, 0.65) captures the population proportion of American adults who believe that the US will be cashless in their lifetimes. O b. 95% of the American adults fall in the interval (0.59, 0.65). O c. We are 5% confident that the interval (0.59, 0.65) captures the sample proportion of American adults who believe that the US will be cashless in their lifetimes. O d. There is a 95% chance that a randomly selected American adult believes the US will become cashless in their lifetime

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A 2019 poll found that 793 out of 1,012 randomly selected adults in Virginia said protection of the environment should be given priority over development of US energy supplies such as coal. Calculate the estimate of the parameter? O a. 0.2164 O b. 0.7836 O c. 1.012 O d. 793