Which type(s) of reliability coefficient(s), if any, would be a major source of information needed to answer each of the following questions?

1. A teacher wonders whether her student Meghan's test score could be a result of her having an off day.

2. An eighth-grade teacher wonders whether the students' aptitude test scores will predict their success in ninth grade.

3. A tenth-grade English teacher wonders whether the grades he assigns to his students' essays are equivalent to the grades his colleague would assign them.

4. A twelfth-grade physics teacher wonders whether her final exam this year is equivalent to her final exam last year.

5. An eighth-grade English teacher has students create portfolios of their work over the semester. Using the portfolios, she classifies the students into three groups: excellent, satisfactory, and unsatisfactory. The teacher wonders whether her classification of students can be made with fewer errors.