Suppose a large population has a mean μand standard deviation σ, and a simple randomsample of size nis taken. The sampling distribution of the sample mean xhas mean andvariance respectively equal to (a) μ/nand σ2/n. (b) μand σ/n. (c) μ/nand σ2/n2. (d) μand σ2/n.

(d) μ and σ²/n

Step-by-step explanation:

In a sampling distribution of sample means, the mean is equal to the population mean, which is μ.

The standard deviation of the sampling distribution of sample means is given by

σ/√n.

The variance of a distribution is the square of the standard deviation; this means the variance of the sampling distribution of sample means would be

(σ/√n) ² = σ² / (√n) ² = σ²/n