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.
Market economies are based on market forces like supply and demand. Mixed economies fall in the middle of market and command economies (where economic choices are governed by some central entity usually the government). The former Soviet Union (USSR) is an example of a command economy where economic choices (what to buy, sell and produce) where made by the government. If Australia is becoming more of a market economy and less of a mixed economy, fewer decisions are made by the government. Here's a diagram of two major types of economies:
Command Economy <-------------- Mixed Economy --------> Market Economy
(Government makes the decisions) (A little of both) (Individuals decide)
A. it moves freshwater more than 100 miles into the ocean
<span>With a diameter that's 11 times larger than Earth's, _______ is the largest planet
It's D. Jupiter is Eleven times larger and is by far the largest planet.</span>
Answer:
A wide range of migration data is collected and disseminated in Europe at national and, sometimes, subnational level. Institutional and legal frameworks have been developed by the European Union (EU) with the aim of ensuring that migration data are of high quality, comparable across countries as a result of harmonization (as established in the legal basis) and easily accessible. A continuous process of political dialogue is in place to ensure that the frameworks keep pace with increased demands for information and knowledge.
Explanation:
