Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: Fats may be either saturated or unsaturated. A saturated fat is a fat that consists of triglycerides whose carbon chains consist entirely of carbon-carbon single bonds. Therefore, the carbon chains are saturated with the maximum number of hydrogen atoms possible. An unsaturated fat is a fat that consists of triglycerides whose carbon chains contain one or more carbon-carbon double bonds . A fat with one double bond is called monounsaturated, while a fat with multiple double bonds is called polyunsaturated (see Figure below ). Answer: saturated and unsaturated

Answer: What are the two types of fats?

Question: Passage: Physical properties include color, density, hardness, and melting and boiling points. Answer: physical

Answer: Hardness, density, color, and melting and boiling points are all considered what types of properties?

Question: Passage: Air quality is a measure of the pollutants in air. Poor air quality started to become a serious problem during the Industrial Revolution. After 1900, motor vehicles added greatly to the problem. The Clean Air Act of 1970 improved the quality of the air over the U. S. Answer: pollutants

Answer:
Air quality is a measure of what in the air?