Based on a​ poll, 70​% of Internet users are more careful about personal information when using a public​ Wi-Fi hotspot. What is the probability that among randomly selected  4 Internet​ users, at least one is more careful about personal information when using a public​ Wi-Fi hotspot? How is the result affected by the additional information that the survey subjects volunteered to​ respond?

By a small margin, Facebook remains the top choice of social media over all ages, with 29% using Facebook most often among those using social media sites. However, more visually oriented social networks such as Snapchat and Instagram continue to draw in younger audiences. When asked "Which one social networking brand do you use most often?" the results in the table show the top brands chosen by Americans aged 12-34 who currently use any social networking site or service. Social M edia Site Faceboo k Snapchat Instagra m Twitter Percentage That Use Most Often 29 28 26 6 20 (a) What is the sum of the percentages for these top social media sites? Give your answer as an exact number. Macmillan Learning top social media sites: What percent of Americans aged 12-34 use other social media sites most often? Give your answer as an exact number. other social media sites: do %

A research institute poll asked respondents if they felt vulnerable to identity theft. In the poll, n = 1026 and x = 520 who said “yes." Use a 95% confidence level. Find the best point estimate of the population proportion p

A researcher gathered a sample of participants who volunteered for a studying of phobias. She measured anxiety level of participants as they viewed photos of spiders and again when they viewed puppies. Which statistical test is appropriate for this study and why?