An influencer is trying to increase subscription for first-time visitors, exposing 1% of these visitors to a new homepage design. Of 752 randomly sampled visitors over a month who saw the new homepage, 64 subscribed.

a) Check any conditions required for constructing a confidence interval.

b) Compute standard error.

c) Construct and interpret a 90% confidence interval for the fraction of first-time visitors of the homepage who would subscribe under the new design (assuming stable behaviors by new visitors over time).