Answer:OBSERVING IS WHATCHING A OBJECT VERY CLOSELY AND EXPIERIMENTING IS WER YOUTEST ON A CERTAIN THING OR CREATURE OR MASS OR ELEMENT
Explanation:IM THE MYSTERY MAN WHOOSH
Answer:
The mass of the massive object at the center of the Milky Way galaxy is 
Explanation:
Given that,
Diameter = 10 light year
Orbital speed = 180 km/s
Suppose determine the mass of the massive object at the center of the Milky Way galaxy.
Take the distance of one light year to be 9.461×10¹⁵ m. I was able to get this it is 4.26×10³⁷ kg.
We need to calculate the radius of the orbit
Using formula of radius



We need to calculate the mass of the massive object at the center of the Milky Way galaxy
Using formula of mass

Put the value into the formula


Hence, The mass of the massive object at the center of the Milky Way galaxy is 
Answer:
The three types of thermal expansions are Linear expansion , Superficial expansion and Cubical expansion
Answer:

Explanation:
Using Newton's second law, we calculate the magnitude of the electric force between the spheres:

The magnitude of the charge in both spheres is the same. So, we calculate the charge, using Coulomb's law:

<span>Creating plasma can be dangerous because of the high amount of ENERGY needed to create it.</span>