solution:
a) The population of interest is all the adults
b) The parameter of interest is p, the proportion of adults who own a cell phone
c) The statistic is the proportion, p^, of the sample of 1572 adults who own a cell phone. The value of the sample proportion is 0.83.
d) We dont the the exact proportion with 100 % but we know that the proportion would lie in a certain range with certain degree of confidence