Need to know 4B Percentage. Thank you!

4. Assume that a manager from Google wants to determine the current percentage of U.S. adults who believe that Google is the best search engine worldwide. The manager tries to find out how many adults must be surveyed in order to be 99% confident that this research is in error by no more than 5 percentage points. A. What is the sample size n if a similar research was conducted by another company and found that 67% of people in the US believed that Google is the best search engine worldwide? B. What is the sample size n if the percentage of U.S. adults who believe that Google is the best search engine worldwide has never been studied and thus not known