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:
In the coustoms hall at tashkurgan, the last town on the road from china's xinjiang province into pakistan, I felt a by-now familiar sense of trepidation. The karakoram highway, also known as the friendship highway in china, was built by the government of pakistan and china. It was started in 1959 and public in 1979. The china-pakistan border is 592 kilometre (368mi) and runs west-east from the disputed tripoint with afghanistan to the disputed tripoint with india in the vicitrity of the siachen glacien.
Answer:
glass like.
Explanation:
Like obsidian, if you break it it will be really sharp.
I believe the answer is False
I think they are just giving away free points
