Surgical complications: A medical researcher wants to construct a 99.8% confidence interval for the proportion of knee replacement surgeries that result in complications. (a) An article in a medical journal suggested that approximately 5% of such operations result in complications. Using this estimate, what sample size is needed so that the confidence interval will have a margin of error of 0.05? A sample of operations is needed to obtain a 99.8% confidence interval with a margin of error of 0.05 using the estimate 0.05 forp. (b) Estimate the sample size needed if no estimate ofp is available. A sample of [j operations is needed to obtain a 99.8% confidence interval with a margin of error of 0.05 when no estimate ofp is available