Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: The bottom two chambers of the heart are called the left and right ventricles. The ventricles receive blood from the atria and pump it out of the heart, either to the lungs or to the rest of the body. Answer: ventricles

Answer: What structures receive blood from the atria and pump it out of the heart?

Question: Passage: Electromagnetic waves vary in their wavelengths, frequencies, and energy levels. The full range of electromagnetic waves makes up the electromagnetic spectrum. Answer: electromagnetic spectrum

Answer: What do we call the full range of electromagnetic waves?

Question: Passage: The highest-numbered shell is the third shell, which has 2 electrons in the 3s subshell and 3 electrons in the 3p subshell. That gives a total of 5 electrons, so neutral phosphorus atoms have 5 valence electrons. The 10 remaining electrons, from the first and second shells, are core electrons. Answer: five

Answer:
How many valence electrons do neutral phosphorus atoms have?