Posted by **Sara** on Tuesday, May 3, 2011 at 9:03pm.

The monthly earnings of teachers is normally distributed with a mean of $3,000 and the standard deviation of $250. We select a sample of 87 teachers. The sampling distribution of the sample mean has an expected value and standard deviation of:

a.) 3,000 and 26.8

b.) 3,000 and 1.69

c.) 3,000 and 250

d.) 3,000 and 2.87

e.) 3,000 and 321.6