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

Answer: How are bacteria identified and classified?

Question: Passage: Carbohydrates include sugars, starches, and fiber. Sugars and starches are used by the body for energy. One gram of sugar or starch provides 4 Calories of energy. Fiber doesn't provide energy, but it is needed for other uses. At age 13 years, you need about 130 grams of carbohydrates a day. Figure below shows good food sources of each type. Answer: 4

Answer: How many calories of energy does one gram of sugar or starch provide?

Question: Passage: The force that a magnet exerts is called magnetic force. The force is exerted over a distance and includes forces of attraction and repulsion. A magnet can exert force over a distance because the magnet is surrounded by a magnetic field. Answer: magnetic force

Answer:
What force includes forces of attraction and repulsion?