Use the following sample to estimate a population mean . 47.1 103.4 64.7 85.7 64.8 79.3 69.9 114.5 73.5 67.2 75.6 68.6 Assuming the population is normally distributed, find the 90% confidence interval about the population mean. Enter your answer as an open-interval (i.e., parentheses) accurate to two decimal places. 90% C.I. =