Use the one-proportion z-interval procedure to find the required confidence interval. Be sure to check the conditions for using that procedure.
A harris poll of 1010 U.S. adults was conducted by telephone on April5-10, 2005. Of those surveyed, 140 had experienced the death of at least one family member or close friend within the last 10 years who died after the removal of life support. Find a 90% confidence interval for the proportion of all U.S. adults who had experienced the death of a least one family member or close fiend within the last 10 years after life support had been withdrawn.