Combine the given two facts to write a concluding fact. Note that there should be some parts of the first and second facts that are not mentioned in this conclusion fact. Your combined fact should be the result of a chain between the two facts. Chains form when two facts connect together to produce a concluding fact. An example of a chain is: "pesticides cause pollution" (fact1) + "pollution can harm animals" (fact2) → "pesticides can harm animals" (conclusion fact). Parts of the concluding fact overlap with the first and the second fact. To construct such a  concluding fact, a useful way is to borrow the subject from one fact and the ending conclusions from another fact.

Q: Fact 1: living underground can be used for hiding from predators. 
Fact 2: Predator and prey play a deadly game of hide and seek.

A: Living underground can be used to avoid playing a deadly game of hide and seek.
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Q: Fact 1: planting trees has a positive impact on an ecosystem. 
Fact 2: Biodiversity encourages a healthier ecosystem.

A: planting trees has a positive impact on biodiversity.
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Q: Fact 1: when a gas in an open container evaporates , that gas spreads out into the air. 
Fact 2: Air is the fluid of gas molecules slamming into one another trying to spread out.

A:
when a gas in an open container evaporates gas molecules slamming into one another.
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