Answer:
There are clusters of galaxies, and the space between them is filled with hot gas, which can only be seen as X-rays or gamma rays.
When measuring how much gas there is between those galaxies, scientists realized that the material should be around five times what can be detected. That undetected matter is known as dark matter.
Answer:
I can't give you an exact answer but I suggest telling him/her something you want to go do after leaving in senior high school.
Explanation: For example " Hey! I want to go on a nice vacation with my family! After that I might have a party with friends, and have a bonfire! What about you?"
Answer:
1. There are people who don't like Halloween.
2. There are 5 people going with us to the movie.
5. Jane will arrive at the party at 7 pm.
6. Dr. Jones has begun to treat the cut.
Explanation:
I only know a few