Exhibit 7-6: a Group of Researchers Hypothesizes That Listening to Music

Multiple Choice

Exhibit 7-6: A group of researchers hypothesizes that listening to music while studying for an exam influences test scores.They randomly selected 28 subjects and divided them into four groups.All groups studied silently for a test for an hour a day for a week.Group 1 studied without music.Group 2 studied with classical music in the background, Group 3 with country, and Group 4 with jazz.The following are the final test scores:
$\begin{array}{l}\begin{array}{lll}\text { Group 1 } & \text { Group 2 } \\50 & 59 \\45 & 57 \\42 & 57 \\41 & 55 \\40 & 56 \\39 & 53 \\38 & 51\end{array}\begin{array}{lll}\text { Group 3} & \text { Group 4 } \\60 & 49 \\56 & 45 \\56 & 45 \\55 & 42 \\54 & 41 \\51 & 39 \\50 & 37\end{array}\end{array}$

-Refer to Exhibit 7-6.What is the null hypothesis?

A) $\mu$ _{Group 1} $\geq$ ( $\mu$ _{Group 2} + $\mu$ _{Group 3} + $\mu$ _{Group 4}) /3
B) $\mu$ _{Group 1} $\leq$ ( $\mu$ _{Group 2} + $\mu$ _{Group 3} + $\mu$ _{Group 4}) /3
C) $\mu$ _Group1 = $\mu$ _{Group 2} = $\mu$ _{Group 3} = $\mu$ _{Group 4}
D) None of these are true.