In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.
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Question: Question: Gerald laid down many rock layers. The layers on the bottom level were likely laid 
 Answer: first

Answer: Lower rock layers were laid down earlier, so they are assumed to contain older fossils.


Question: Question: If an animal is able to eat food more difficult is it more or less likely to reproduce? 
 Answer: less

Answer: Natural selection is the process by which living things with beneficial traits produce more offspring, so their traits become more common over time.


Question: Question: Compared to the Sun, a yellow dwarf star, would the blue super giant star Rigel be 
 Answer: hotter?

Answer:
But, in stars, the bluer the star, the hotter it is, and the redder it is, the older and colder it is.