For a particular brand of TV picture tube, it is known that the mean operating life of the tubes is μ = 9,000 hr with a standard deviation of σ = 500 hr. (a) Determine the expected value and standard...

For a particular brand of TV picture tube, it is known that the mean operating life of the tubes is μ = 9,000 hr with a standard deviation of σ = 500 hr. (a) Determine the expected value and standard error of the sampling distribution of the mean given a sample size of n = 25. (b) Interpret the meaning of the computed values.