please answer both

A marketing researcher for a phone company surveys 300 people and finds that the proportion of clients who are likely to switch providers when their contract expires is 0.14. a) What is the standard deviation of the sampling distribution of the proportion? b) If she wants to reduce the standard deviation by half, how large of a sample would she need? a) The standard deviation of the sampling distribution of the proportion is (Round to three decimal places as needed.) An investment website can tell what devices are used to access the site. The site managers wonder whether they should enhance the facilities for trading via "smart phones", so they want to estimate the proportion of users who access the site that way (even if they also use their computers sometimes). They draw a random sample of 100 investors from their customers. Suppose that the true proportion of smart phone users is 34%. a) What would the standard deviation of the sampling distribution of the proportion of the smart phone users be? 0.047 (Round to three decimal places as needed.) b) What is the probability that the sample proportion of smart phone users is greater than 0.347 (Round to three decimal places as needed.)