Give a practical interpretation of the interval, part a. a. with 10% confidence, the true mean failure time of used colored display panels is between the endpoints of the confidence interval. b. with 90% confidence, the true mean failure time of used colored display panels is outside the endpoints of the confidence interval. c. with 90% confidence, the true mean failure time of used colored display panels is between the endpoints of the confidence interval. d. with 10% confidence, the true mean failure time of used colored display panels is outside the endpoints of the confidence interval. e. an interpretation cannot be determined.