The time required by a specialized workforce to assemble 100 units of the same type of transistorized assembly was measured. The average time was 10.2 minutes with a standard deviation of 1.8 minutes. What is the lower limit of the confidence interval for the actual average time of assembly at the 90% confidence level? - 9.94 - 9.90 - 9.85 - 9,97 - 9,74