A sample mean is computed from a population with a variance of 2.45. The sample size is 40. The standard error of the sample mean is closest to:
A.0.039 B.0.247 C.0.387正确答案B
A sample mean is computed from a population with a variance of 2.45. The sample size is 40. The standard error of the sample mean is closest to:
A.0.039 B.0.247 C.0.387正确答案B
