An investor wants to estimate the population mean earnings of stocks in the financial services sector. Assuming

the population standard deviation of earnings is σ=$1,250 {“version”:”1.1″,”math”:”sigma = $1,250″}, a confidence interval for which of the following would be best for this task?

Question 4 options:

μ {“version”:”1.1″,”math”:”mu”}, when σ {“version”:”1.1″,”math”:”sigma”} is known

μ {“version”:”1.1″,”math”:”mu”}, when σ {“version”:”1.1″,”math”:”sigma”} is unknown

The true mean of the differences, for paired data

The difference between two means, using independent samples

One proportion

The difference between two proportions

Linear regression