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

[Q]: Passage: The alkaline earth metals include beryllium, magnesium, calcium, strontium, and barium. Strontium and barium react with air and must be stored in oil. Answer: alkaline earth metals
[A]: Beryllium, magnesium, calcium, strontium, and barium are classified as what type of metals?

[Q]: 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
[A]: What structures receive blood from the atria and pump it out of the heart?

[Q]: Passage: Earthquake magnitude affects how much damage is done in an earthquake. A larger earthquake damages more buildings and kills more people than a smaller earthquake. But that's not the only factor that determines earthquake damage. The location of an earthquake relative to a large city is important. More damage is done if the ground shakes for a long time. Answer: magnitude
[A]:
What general property of an earthquake is used to describe its relative strength?