The awnser isthird bright band and it is constructive
The spiral structure emerges when galactic clusters (open), H II regions and O & B type stars (young stars) are used as tracers. We know this to be true as other pinwheel galaxies exhibit the same patterns across these tracers as in the milky way.
Answer:
It is directed inward, toward the center of a circle.
Two types of mechanical waves: longitudinal<span> waves and </span>transverse<span> waves; the medium movement differs between the two.
</span>In a longitudinal wave the medium particle movement is parallel to the direction of wave propagation; example is sound wave in air.
I<span>n a transverse wave the medium particle movement is perpendicular to the direction of wave propagation; example is mechanical wave on a string.
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