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. [4 pts] What is the confidence interval for the difference in open rate?

[1 pts] Is this difference significant?

c. [4 pts] What is the confidence interval for the difference in click rate?

d. [1 pts] Is this difference significant?

e. [4 pts] 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.