Mass of the milkyway galaxy :

The magnitude of the mass of the Milky Way galaxy = 
<h3>Can galaxies recycle stars?</h3>
Galaxies do not appear to have sufficient matter inside them to keep shaping modern stars at the rates that they do. Presently, astronomers have caught a universe within the act of reusing fabric that it already tossed out, which may clarify the discrepancy. New perceptions give the primary coordinate evidence of gas streaming into distant galaxies that are effectively making infant stars, offering support for the "galactic recycling" theory.
To learn more about galactic recycling, visit;
brainly.com/question/6272572
#SPJ4
Answer:
2.The density of air increases and thendecreases as the sound wave passes.
Explanation:
Sound waves are mechanical waves, which consist of oscillation of the particles in the medium where the wave is transmitted through.
Sound waves are also longitudinal waves, which means that the direction of oscillations of the particles of the medium occurs in a direction parallel to the direction of motion of the wave (so, essentially back and forth).
Due to the nature of longitudinal waves, they create alternating regions of the medium where the density of particles are higher and lower. The former are called compressions, while the latter are called rarefactions.
Therefore, when a sound wave travels through the air, the density of one region of air continuously changes: compression first (high density), rarefaction then (lower density), then compression again, etc..
An explanation of sound<span> waves. The pitch of a </span>sound<span> is dictated by the frequency of the </span>sound<span> wave, while the loudness is dictated by the </span>amplitude<span>. When a drum is beaten, the air particles around the drum skin vibrate in the form of a compression wave</span>
Answer:
A student could conclude that the cart gained momentum as it rolled down.
Explanation:
If the cart was allowed to roll down the ramp from rest, it means that the initial velocity of the cart is zero (0). Also, if the final velocity of the cart became 25 cm/s, it means that the velocity of the cart increased from 0 to 25 cm/s.
Therefore, A student could conclude that the cart gained momentum as it rolled down.