The owner of Touchdown Sports Bar wants to develop a time standard for the task of mixing a specialty cocktail. In a preliminary study, he observed one of his bartenders perform this task seven times with an average of 90 seconds and a standard deviation of five seconds. How many observations should be made if he wants to be 95.44 percent confident that the maximum error in the observed time is one second? ? Answer is one of these # 64 ? 86 ? 100 ? 144 ? 169