In what year did the roman republic end and the roman empire begin

Clouds thar look like whisps of hair are

How did the government restrict immagration in the 1920

What important discovery was made by edmond halley and alexis clairaut, using newton's ideas of mathematics and gravity? they created the scientific method to outline how science should be conducted. they were able to find the orbit of a comet and predict the year of its return. they discovered the three newest planets--uranus, neptune, and pluto. they explained why objects appear to have color.