Set up the expression. The sum of twice a number
and negative eight.

B. the reader cannot accurately assess the airline because the evaluations are not necessarily representative of all evaluations.D. the reader cannot accurately assess the airline without reading all the evaluations.

Step-by-step explanation:

Using the most positive and the most negative comments to evaluate the airlines will not be an accurate measure of the airline because these are not a good enough sample. The opinions of those who fall in-between the most positive and negative should also be included as they could have some vital details as well.

Also, in order to be completely accurate, all the comments of the airline should have been posted because this would represent the entire population of comments and so would give the best assessment.