Surgical complicaons: A medical researcher wants to construct a 98% condence interval for the proportion of knee replacement surgeries that result in complications. (a) An article in a medical journal suggested that approximately 20% of such operations result in complications. Using this estimate, what sample size is needed so that the condence interval will have a margin of error of {108? A sample of E] operations is needed to obtain a 98% condence interval with a margin of error of 0.08 using the estimate 0.2 for p