Answer:
The H-R diagram can be used by scientists to roughly measure how far away a star cluster or galaxy is from Earth. This can be done by comparing the apparent magnitudes of the stars in the cluster to the absolute magnitudes of stars with known distances (or of model stars).
Friction I believe is the answer
hope this helps
Answer:
B: beaks, finches.
Explanation:
Beaks, finches. This is because he noticed that fruit-eating finches had beaks similar to parrots, while finches that ate insects had narrow beaks. The difference in their beaks is due to adapting to different environments which causes them to evolve into different species of finches.
