8. the manager of the local hamburger express wishes to estimate the mean time customers spend at the drive-through window. a sample of 20 customers experienced a mean waiting time of 2.65 minutes, with a standard deviation of 0.45 minutes. a. develop a 90 percent confidence interval for the mean waiting time. 9. in a sample of 200 residents of georgetown county, 120 reported that they believed the county real estate taxes were too high. a. develop a 95 percent confidence interval for the proportion of residents who believe the tax rate is too high. b. would it be reasonable to conclude that the majority of the taxpayers feel that the taxes are too high? 10. briefly (3-4 sentences) state at least one real world application of the module 2 concepts and any application to your workplace.