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

Q: Passage: Did you ever have a picnic ruined by a surprise rainstorm? People often complain when the weather forecast is wrong. But in fact, weather forecasts today are much more accurate than they were just 20 years ago. Scientists who study and forecast the weather are called meteorologists . How do they predict the weather?. Answer: meteorologists

A: What do we call scientists who study and forecast the weather?
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Q: Passage: Only the top 200 meters or so of water receive enough sunlight for photosynthesis. This part of the water is called the photic zone. Below 200 meters, there is too little sunlight for photosynthesis to take place. This part of the water is called the aphotic zone. In this zone, food must come from other sources. It may be made by chemosynthesis, in which microorganisms use energy in chemicals instead of sunlight to make food. Or, food may drift down from the water above. Answer: photic zone

A: What is the top part of water able to receive enough sunlight for photosynthesis called?
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Q: Passage: The electrons in the outer energy level of an atom are called valence electrons . It is valence electrons that are potentially involved in chemical reactions. The number of valence electrons determines an element's reactivity, or how likely the element is to react with other elements. The number of valence electrons also determines whether the element can conduct electric current. That's because electric current is the flow of electrons. Table below shows how these properties vary in elements from each class. Answer: valence electrons

A:
What are electrons in the outer energy level of an atom called?
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