Data Set 10-7: in That Long Standing Feud Between the Hatfields

Multiple Choice

Data Set 10-7: In that long standing feud between the Hatfields and the McCoys, Old Doc Sawbones has been keeping score. During the last 16 years he noted in his feudian notebook a "degree of injury"
measure each time he patched up, sewed up, or made a coroner's report on anyone in the two families. Summary statistics were:
$$\begin{array} { c c c } & \text { Hatfields } & \text { McCoys } \\\bar { X } & 41 & 34 \\\hat { S } & 6 & 8 \\N & 16 & 16\end{array}$$
-The standard error of the difference of the data in Data Set 10-7 is

A) 6.25
B) 1.87
C) 0.625
D) 2.50