How does the appearance of spiral galaxies vary? Select the two correct answers.(1 point)

Responses

They vary in how tightly their arms are wound.
They vary in how tightly their arms are wound.

They vary in the brightness of stars located on their arms.
They vary in the brightness of stars located on their arms.

Some are more elongated in shape than others.
Some are more elongated in shape than others.

Some have a band of stars and materials through their middle, but others do not.
Some have a band of stars and materials through their middle, but others do not.