Even more on determining hypotheses

In  each of the following situations, state an appropriate null hypothesis H0 and alternative hypothesis Ha. Be sure to identify the parameters that you use to state the hypotheses. (We have not yet learned how to test these hypotheses.)

(a)  A sociologist asks a large sample of high school students which academic subject they like best. She suspects that a higher percent of males  than  of females will name marketing as their favorite subject.

(b)   An education researcher randomly divides sixth-grade students into two groups for physical education class. He teaches both groups basketball skills, using the same methods of instruction in both classes. He encourages Group A with compliments and other positive behavior but acts cool and neutral toward Group B. He hopes to show that positive teacher attitudes result in a higher mean score on a test of basketball skills than do neutral attitudes.

(c)   An education researcher believes that among college students there is a negative correlation between credit card debt and self-esteem. To test this, she gathers credit card debt information and self-esteem data from a sample of students at your college.