According to a report, 65% of parents of teens aged 13 to 17 said that they had checked which web sites their teens had visited. The 65% figure was based on a sample of1,040parents of teens in this age group.(a)What additional assumption must be made in order for it to be appropriate to use the formula of this section to construct a confidence interval to estimate the proportion of all parents of teens aged 13 to 17 who have checked which web sites their teens visit?We need to assume that there are only 676 parents of teens aged 13 to 17 who checked which web sites their teens had visited.We need to assume that 65% of 1,040 is greater than or equal to 10. We need to assume that all parents of teens aged 13 to 17 in the population have been surveyed.We need to assume that the 1,040 people formed a random sample of parents of teens aged 13 to 17.(b)Construct a 90% confidence interval for the proportion of all parents of teens aged 13 to 17 who have checked which web sites their teens visit. (Round your answers to three decimal places.)

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Interpret the interval.There is a 90% probability that the proportion of all parents of teens aged 13 to 17 who have checked which web sites their teens visit is directly in the middle of these two values.We are 90% confident that the proportion of all parents of teens aged 13 to 17 who have checked which web sites their teens visit is directly in the middle of these two values. We are 90% confident that the proportion of all parents of teens aged 13 to 17 who have checked which web sites their teens visit outside these two values.We are 90% confident that the proportion of all parents of teens aged 13 to 17 who have checked which web sites their teens visit is between these two values.There is a 90% probability that the proportion of all parents of teens aged 13 to 17 who have checked which web sites their teens visit is between these two values.(c)Would a 99% confidence interval be narrower or wider than the interval computed in part (b)? Justify your answer.As the level of confidence increases, the critical value ---Select--- increases decreases ,so the confidence interval becomes ---Select--- narrower wider .