Practice makes perfect! You'll only get better by working hard! :)
Empirical data are gathered from experiments. This does not hold true for all species at all times. But the only way to know a certain datum for a certain specie at a certain situation, you do an experiment. However, theoretical data is more on the theory or concept of the situation. It formulates a general equation that could as much as possible hold true to all.
Therefore, this data is empirical.
The answer is A.
That would be A. -8 x 1 = -8
I'm pretty sure it's the second and third one!