An economist is interested in studying the incomes of consumers in a particular region. The population standard deviation is known to be $5,000. A random sample of 100 individuals resulted in an average income of $150,000. What total sample size would economist need to use for a 99% confidence interval if the overall width of the interval should not be more than $500 ? A) n=1537 B) n=385 C) n=384 D) n=1536