Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Each hemisphere of the cerebrum is divided into four parts, called lobes. The four lobes are the:. Answer: 4

Answer: How many lobes is each hemisphere of the cerebrum divided into?

Question: Passage: Population density is the average number of individuals in a population per unit of area or volume. For example, a population of 100 insects that live in an area of 100 square meters has a density of 1 insect per square meter. If the same population lives in an area of only 1 square meter, what is its density? Which population is more crowded? How might crowding affect the health of a population?. Answer: population density

Answer: What is the term for the average number of individuals in a population per unit of area or volume?

Question: Passage: The Sun was the first object to form in the solar system. Gravity pulled matter together to the center of the disk. Density and pressure increased tremendously. Nuclear fusion reactions begin. In these reactions, the nuclei of atoms come together to form new, heavier chemical elements. Fusion reactions release huge amounts of nuclear energy. From these reactions a star was born, the Sun. Answer: sun

Answer:
What was the first object to form in the solar system?