An April 2009 survey of 2253 American adults conducted by the Pew Research Center's Internet & American Life Project revealed that 1262 of the respondents had at some point used wireless means for online access. 1 Calculate an interpret a 95% CI for the proportion of all American adults who at the time of the survey had used wireless means for online access. 2 What sample size is required if the desired width of the 95% CI is to be at most 0.04, irrespective of the sample results? 3 Does the upper limit of the interval in (a) specify a 95% upper confidence bound for the proportion being estimated?