please answer:)

. In 2010, the CDC reported that 20% of Americans smoked tobacco. . A more recent random sample of 400 Americans, found that 76 smoked. - Is the proportion of American's who smoke less since 2010, at a = .1? - Has the proportion of American's who smoke changed since 2010, at a = .1? - What would happen if you increased "n" to 4000 and "x" was 760 (i.e. the same proportion but a larger sample)