Nine software engineers were interviewed to develop an estimate for software lines of code. The mean estimate is 12480 lines of code with a standard deviation of 2400 lines of code. Develop an 90% confidence interval for the population mean. (Carry intermediate calculations to three decimal places.)
11374 ≤ μ ≤ 13586
10992 ≤ μ ≤ 13968
11769 ≤ μ ≤ 13191
11362 ≤ μ ≤ 13598