If the sum of all the wages, in dollars, is given by Z X = 498 960 , how many workers were in the sample? O a. n = 96 O b. n = 70 O c. n = 54 O d. n = 100 An estimate of population mean may be given by two numbers, between which the population mean is considered to lie. This kind of estimate is called a/an: O a. efficient estimate O b. point estimate O c. biased estimate O d. interval estimate