Ateacher finds the distribution of scores on a final exam to be positively skewed with low variability. on the basis of this information, the teacher would be most justified in concluding that
1. a small number of students in the class did poorly on the exam
2. the students in her classroom have a very wide range of intellectual abilities
3. the exam was too difficult
4. the exam is not a reliable assessment tool
5. most of her students are of above average ability