Based on survey results from 750 Twitter users, the following was reported: "With 99% confidence, it has been estimated that somewhere between 47.3% and 56.7% of all Twitter users use this social media platform as their primary source of news."

1.)What number of Twitter users (out of the 750 sampled) use Twitter as their primary source of news?

375 of the sampled Twitter users

390 of the sampled Twitter users

50% of the sampled Twitter users

52% of the sampled Twitter users

Unable to determine because the results of the study were not provided.

2.) What is the margin of error for the reported 99% confidence interval?

0.473

0.52

0.567

0.047

1.04

3.) Facebook would like to perform a similar survey among Facebook users. If a 90% confidence level is to be used and the desired conservative margin of error is 5%, what is the minimum sample size that would be required?