According to a censusbureau,13.5%of the population in a certain country changed addresses from 2008 to 2009. In2010,1818out of a random sample of 200citizens of this country said they changed addresses during the previous year(in 2009).

a)A 99%confidence interval to estimate the actual proportion has a lower limit of _____ and an upper limit of _____.

b) The margin of error is _____.