<span>Unexpected orbital velocities of stars around the centers of galaxies led astronomers to predict the existence of dark matter. Dark matters are hypothetical substance that are believed to account for around five-sixths of the matter in the universe.</span>
Protons, neutrons, and electrons<span> are the three main subatomic particles found in an atom. Protons have a</span>positive<span> (+) </span>charge<span>. An easy way to remember this is to remember that both proton and </span>positive<span> start with the</span>letter<span> "</span>P<span>." Neutrons have no electrical </span>charge<span>.</span>
Kinetic energy = 1/2mv2
= 1/2 x 2 x 3^2
= 9J
Answer:
2000metres
Explanation:
Pressure= density x height x gravity
Gravity is always a constant = 10N/kg
so height= Pressure/( density x gravity)
h= 20000000/(1000 x10)
h= 2000 metres
