Annual starting salaries for college graduates with degrees in business administration are generally expected to be between $10,000 and $45,000. Assume that a 95% confidence interval estimate of the population mean annual starting salary is desired. a. What is the planning value for the population standard deviation? O = b. How large a sample should be taken if the desired margin of error is $300? Round your answers to next whole number. $190? $140? c. Would you recommend trying to obtain the $140 margin of error? Explain. No, the sample size would probably be too time consuming and costly