A Researcher Draws a Random Sample of 100 Full-Time City

Multiple Choice

A researcher draws a random sample of 100 full-time city employees and, based on their self-reported salaries, calculates an average annual salary of $56,000. According to city records, however, the average annual earnings of all full-time city employees is $51,000. Which of the following conclusions can you draw from these data?

A) The mean of the sampling distribution for samples of 100 is $51,000.
B) The estimated margin of error for all samples of 100 is $5,000.
C) The sample estimate is based on a biased sample of city employees.
D) The sample is too small to provide an accurate estimate of the average earnings of all employees.