A researcher realizes that he has been favoring the participants in Condition B by smiling at them more than he smiles at participants in Condition A. This is a threat to the experiment because it introduces:

first, the romans stayed isolated because they had to defend their own territories from neighboring cities that were harassing them, like the etruscans. second, once the romans managed to defeat their neighbors, and started to expand their territory, they started to build roads and bridges. finally, now that the romans have covered their territory with roads functioning as highways, they could mobilize their legions faster to assemble larger military units in a specific place.

answer; john stuart mill's principle of utility is your answer; /// good luck

where are the choices

answer; observing;