A Group of College Students Believes the Average Grades in Psychology

Multiple Choice

A group of college students believes the average grades in psychology courses are different than the average grades in biology courses. The group found the average
Psychology grades of a sample of 11 students was 82.4 and the average biology grades of
A sample of 11 students was 81.2. What is the null hypothesis for this study?

A) $H _ { 0 } : \mu _ { \text {psychology } } = \mu _ { \text {biology } }$
B) $H _ { 0 } : \mu _ { \text {psychology } } + \mu _ { \text {biology } } = 163.6$
C) $H _ { 0 } : \mu = 82.4$ and $81.2$
D) $H _ { 0 } : \mu _ { \text {psychology } } = 82.4$ and $H _ { 0 } : \mu _ { \text {biology } } = 81.2$