Answer: is constant
Explanation:
In order to analyze the velocity of the stars within a galaxy, the <u>galaxy rotation curves</u> (developed by the American astronomer Vera Rubin) are used. These graphs are elaborated as a scatter diagram in which the orbital velocity of the stars present in a galaxy is represented on the Y axis and the distance of these stars to the center of the galaxy on the X axis.
Thanks to this diagram, it has been possible to observe a characteristic behavior in the rotation speed of the stars (and gas) present in the galaxies, which differs from the rules of the orbital movement of the planetary systems postulated by Newton and Kepler.
This means that in these galaxy rotation curves it has been observed that the rotation speed of stars and gas is "constant", regardless of the distance to the center of the galaxy. This discrepancy and these results were then used to demonstrate the existence of dark matter in the universe.
The summer monsoon generally begins in April and lasts through late September, while the winter monsoon arrives
in October and ends in March.
A pollitical map focuses on boundaries between entities like countries states of counties they are generally brigther colors to easly distinguish the boundaries a phisical maps focuses on the geography of the area and will often have shaded relief to show the mountains and valleys.
<span>They got it through the Treaty of Paris, at the end of the Seven Years’ War.</span>
Answer:plains,plateaus,mountain B,mountain R
Explanation:
