From coolest to hottest, the seven letters for the star types are ________.
Fill in the blank(s) with correct word
Question 2
Why should galaxy collisions have been more common in the past than they are today?
A) Galaxies were closer together in the past because the universe was smaller.
B) Galaxies attracted each other more strongly in the past because they were more massive; they had not yet turned most of their mass into stars.
C) Galaxies were more active in the past and therefore would have collided with each other more frequently.
D) Galaxies were much bigger in the past since they had not contracted completely.
Types of neurons.
Different Types of Cells
Types of worms
Balmer Lines in the Spectrum of a Star
Types of Respiratory Protection Devices