A 2018 poll of 3631 randomly selected users of a social media site found that 2478 get most of their news about world events on the site. Research done in 2013 found that only 48% of all the site users reported getting their news about world events on this site.

a.

Does this sample give evidence that the proportion of site users who get their world news on this site has changed since2013? Carry out a hypothesis test and use a 0.05 significance level.

b.

After conducting the hypothesistest, a further question one might ask is what proportion of all of the site users get most of their news about world events on the site in 2018. Use the sample data to construct a 95% confidence interval for the population proportion. How does your confidence interval support your hypothesis testconclusion?