Answer:
b. flat rotation curves in spiral galaxies
Explanation:
Dark matter accounts for majority of the matter in the universe (about 85%). It is considered to be composed of subatomic particles which are yet to be discovered. Dark matter cannot be observed because it does not emit light that can be detected. Only its gravitational effect is visible.
Astronomers when calculated the mass of the visible matter and tried to account for the observed speed of stars in the galaxy, there was a mismatch. To understand what caused this mismatch, astronomers gave name to the invisible matter as the Dark Matter.
The expected velocity of stars should decrease away from the near the center of the galaxy but a constant velocity of stars was observed that is a relatively flat rotation curve was obtained.
Thus, flat rotation curves in spiral galaxies in an evidence of Dark Matter.
Answer:
A collection of languages that share a common origin but have since evolved into individual languages is
A language family is a collection of languages related through a common ancestral language existing before recorded history. ... New Englanders use a different dialect of English than other Americans primarily because their ancestors came from different regions of England.
Explanation: This should help
Answer:
The main difference between hot and cold desert is that the hot desert is battered by a high sun whereas the cold desert has ice and the snow in the ground.
Answer:
The city with the most Michelin star restaurants is Tokyo (Japan) with a total of 230 restaurants, according to the 2019 Michelin Guide. As of 7 March 2019, Tokyo has a total of 308 Michelin stars distributed on 230 restaurants.
Answer:
Well it looks like it will be sunny and get drop from 81 to 72 over night and, It will rise again to 81 degrees tomorrow.
Explanation:
