Use the Following Information to Answer the Next Three Questions $\overline{x}$

Multiple Choice

Use the following information to answer the next three questions.
 the population mean (µ) is hypothesized to be 200
 the sample mean ( $\overline{x}$ ) is 220
 the sample size (n) is 25
 the unbiased sample standard ( $\hat{s}$ ) is 15
-The estimated value of the standard error of the mean ( $\frac{s}{x}$ ) is

A) 0.6.
B) 0.9.
C) 1.6.
D) 2.6.
E) 3.0.