Answer:
Because then the city got very crowded and transporting food got difficult to do, so the railways and automobiles made it easy.
Explanation:
<span>how brain chemistry relates to depression</span>
Answer:
multiple variables
Explanation:
Multiple variables entails that there may be more than one dependent variable and/or independent variable.
Such always comes to play out if you are conducting an experiment with multiple stages or sets of procedures.
In such type of experiments, there may be more than one set of measurements with different variables.