Simple question.

while the first industrial revolution saw a change in producing goods using human and animal power to machines, the second industrial revolution of the 19th century saw a change from using to
a. stone; metal
b. iron; steel
c. machines; humans & animals
d. self-learning robots; man-powered simple machines

How long ago was the fall of rome (in years)

Who was the first explorer to sail all the way down the mississippi river

Will mark ! how was the appointment of two consuls during the roman republic an example of a democratic principle?one consul represented patricians and one represented plebeians, so that all citizens had representation. each consul had control over the same number of military legions, which prevented either one from a forceful takeover. consuls had to agree on all decisions, which prevented any one person from gaining too much power. consuls had to make decisions based on majority rule in the senate.