2. You are conducting an A/B test comparing two different versions of a newsletter for a charity with 500 potential donors in each group. The A email has an open rate of 31.1% and a click rate of 16.1%. The B email has an open rate of 31.5% and click rate of 20.2%.

a. What is the confidence interval for the difference in open rate?

b. Is this difference significant?

c. What is the confidence interval for the difference in click rate?

d. Is this difference significant?

e. If you were reporting the results of this test to others at the charity, what would you write in the email? Keep it as short and clear as possible.