question: What sentence would provide a factual answer to this question: "What kind of energy causes evaporation?"

answer: the sun causes water to evaporate more quickly by adding heat


question: What sentence would provide a factual answer to this question: "What is part of an ecological system?"

answer: an ecosystem contains nonliving things


question: What sentence would provide a factual answer to this question: "Birds give birth to their babies while still in an egg. Mammals, however, give birth to their babies"

answer:
mammals give birth to live young