A random sample was taken from the Financial Post list of top 500 companies for 1998. Of 26 food- and beverage-related industries in the sample, 12 had at least 10% foreign ownership. Of 29 wholesale distribution firms in the sample, 15 had at least 10% foreign ownership.
a. Use a 0.01 significance level to test the claim that both industry groups sampled had the same proportion of companies with a foreign ownership level of at least 10%.
b. Construct the 99% confidence interval for the difference between proportions of companies that are significantly (at least 10%) foreign-owned, in top food- and beverage-related companies versus top wholesale distribution firms.