A Random Sample of 500 Reports an Average Yearly Income $\pm$

Multiple Choice

A random sample of 500 reports an average yearly income of $42,000 with a standard deviation of $1000.An estimate of the parameter at the 95% level is about $175 wide.In this research situation,

A) we can be 95% confident that the population mean is 42,000 $\pm$ 175.
B) the sample size is much too small to justify the use of estimation procedures.
C) the alpha level is 1000.
D) the sample mean is $175.