In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.
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Question: Question: Which part of the atmosphere do greenhouse gasses trap heat in? Answer: troposphere

Answer: Troposphere part of the atmosphere do greenhouse gasses trap heat in.


Question: Question: What is the key to the demographic transition? Answer: reduced family size

Answer: Reduced family size is the key to the demographic transition.


Question: Question: The most common two-lens telescope, like the simple microscope, uses lenses of what shape? Answer: convex

Answer:
The most common two-lens telescope, like the simple microscope, uses convex lenses.