Q3. Suppose a random sample of 85 items has been taken from a population and 40 of the items contain the characteristic of interest. a Use this information to determine a 90% confidence interval to estimate the proportion of the population that has the characteristic of interest. (3 marks) (b) Determine a 99% confidence interval. (3 marks) As the level of confidence changes and the other sample information stays constant, what happen to the confidence interval? Explain