A researcher wants to test the hypothesis that childhood exposure to advertising exceeds 111 ads per day. Randomly:r selecting 58 days, they calculated the sample mean, and may know the population standard deviation. The researchers should use the following distribution: 0 Student-t distribution '3' normal [2} distribution 0 Chi-squared distribution Ci Binomial distribution '3' She cannot perform the test as the population standard deviation is not available A researcher wants to estimate the mean exposure to a certain type of internet ads. Originally they found a 99% confidence interval, and then, with all other factors the same, they decreased the confidence level to 90%. As a result... O the confidence interval will become wider O the confidence interval will become narrower O the confidence interval may get wider or narrower O the confidence interval will not change O none of the aboveThe central limit theorem states that... D As sample size increases, the distribution of sample means will approach the binomial distribution 0 As sample size decreases, the distribution of sample means will approach the student t-distributicn D As sample size decreases, the distribution of sample means will approach the binomial distribution Q As sample size increases, the distribution of sample means will approach the student t-distribution D As sample size increases, the distribution of sample means will approach the normal distribution