Given a scientific passage and an answer, generate a question for the given answer.
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Question: Passage: 19.3 The Human Population Earth's human population is growing exponentially. Humans have increased their carrying capacity through technology, urbanization, and harnessing the energy of fossil fuels. The age structure of a population allows us to predict population growth. Unchecked human population growth could have dire long-term effects on human welfare and Earth's ecosystems. Answer: carrying capacity

Answer: Human population is growing exponentially and humans have increased what normally limiting factor through technology, urbanization, and harnessing the energy of fossil fuels?

Question: Passage: The Sun gives off energy in tiny packets called photons . Photons travel in waves. Figure below models a wave of light. Notice the wavelength in the figure. Waves with shorter wavelengths have more energy. Answer: photons

Answer: What are the tiny packets of energy the sun gives off called?

Question: Passage: The fuel that burns in a combustion reaction contains compounds called hydrocarbons. Hydrocarbons are compounds that contain only carbon (C) and hydrogen (H). The charcoal pictured in the Figure above consists of hydrocarbons. So do fossil fuels such as natural gas. Natural gas is a fuel that is commonly used in home furnaces and gas stoves. The main component of natural gas is the hydrocarbon called methane (CH 4 ). You can see a methane flame in the Figure below . The combustion of methane is represented by the equation:. Answer: hydrocarbons

Answer:
What is the name for compounds that contain only carbon and hydrogen?