Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Electrons are always added to the lowest energy level first until it has the maximum number of electrons possible, and then electrons are added to the next higher energy level until that level is full, and so on. The maximum number of electrons at a given energy level depends on its number of orbitals. There are at most two electrons per orbital. Answer: the lowest

A: Electrons are always added to which energy level first?
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Q: Passage: Graphs are very useful tools in science because they display data visually. Three commonly used types of graphs are bar graphs, circle graphs, and line graphs. Each type of graph is suitable for a different type of data. Answer: graphs

A: Bar, circle, and line are examples of what kind of data visualization?
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Q: Passage: Two factors influence the pressure of fluids. They are the depth of the fluid and its density. Answer: depth and density

A:
What two factors influence the pressure of fluids?
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