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

Example Input: Passage: Secondary pollutants form from chemical reactions that occur when pollution is exposed to sunlight. Answer: sunlight
Example Output: Secondary pollutants form from chemical reactions that occur when pollution is exposed to what?

Example Input: Passage: Bacteria are so small that they can only be seen with a microscope. When viewed under the microscope, they have three distinct shapes ( Figure below ). Bacteria can be identified and classified by their shape:. Answer: by their shape
Example Output: How are bacteria identified and classified?

Example Input: Passage: Line graphs are especially useful for showing changes over time. The line graph in Figure below shows how distance from school changed over time when some students went on a class trip. Answer: time
Example Output:
Line graphs are especially useful for showing changes over what?