Answer:
NASA's Chandra X-ray Observatory and other telescopes such as the Hubble telescope.
Explanation:
Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies.
The above observations have provided the strongest evidence yet that most of the matter in the universe is dark.
Explanation:
Acceleration is defined as the change in velocity over time.
When there is an increment or increase in the magnitude of velocity of a moving body then it is known as positive acceleration.
Whereas when there is a decrease in magnitude of velocity of a moving body then it is known as negative acceleration.
Thus, we can conclude that positive acceleration occurs when an object speeds up.
Solid to liquid
Liquid to solid
By adding or removing heat energy aka thermal energy
Krypton ... symbol Kr ... is an element. It's element number 36, because
there are 36 protons in the nucleus of every atom of Krypton.
Krypton has nothing to do with Superman, except that about 75 years ago,
the creators of Superman thought it was a cool-sounding scientific word,
so they chose it for the name of his home planet.