Answer
a) The sample was 2,259 American adults age 18 and older that were surveyed.
b) The sample's population is all the American adults age 18 and older.
c) Reading the news is more accesible now a day through a variety of platforms. Internet and television are now more popular than newspaper and radio.
Work Step by Step
Article: "Survey: More Americans get News from internet than from newspaper or radio." By Doug Gross, CNN
Source:
http://edition.cnn.com/2010/TECH/03/01/social.network.news/index.html
The sample is the subset of the population which would be 2,259 Americans 18 and older out of all the Americans 18 and older.
The inference is drawn from the Survey. "Almost all respondents, 92 percent, said they get their news from more than one platform." and "Only television news still outpaces the Internet, with 78 percent of respondents saying they watch local news and 73 percent saying they view a national network or cable news channel like CNN, Fox News or MSNBC."