Which describes one way that Aristarchus's explanation of the movement of objects in the sky was different from other scientists' earlier explanations?

3. manufacturing institutions, because capitalists  are about making money. 

Which of the following is an example of an opposing signal? no examplthates given.   i would say, that traffic lights in a city at major intersections direct the flow of traffic in opposite directions so would be an example.also, stop signs on either side of the same street would be an example. at a train crossing, the light for allowing car traffic in opposite directions or not would be another example.