2. A tire manufacturer wishes to investigate the tread life of its tires. A sample of 10 tires driven 50,000 miles or more revealed a sample mean of .32 inch of tread remaining with a sample standard deviation of .09 inch. (a) Develop a 95 percent confidence interval for the population mean. Interpret the results. (b) Would it be reasonable for the manufacturer to conclude that after 50,000 miles the population mean amount of tread remaining is .30 inches