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.
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Question: Fact 1: the emission of sulfur dioxide causes acid rain. 
Fact 2: ACID RAIN Acid rain is polluted and harmful to the environment.

Answer: Sulfur dioxide emissions cause pollution and harm to the environment.


Question: Fact 1: rain causes erosion. 
Fact 2: Erosion is the breaking apart and moving of rocks and soil.

Answer: Rain causes the breaking apart and moving of rocks and soil.


Question: Fact 1: Head hair is especially important in preventing heat loss from the body. 
Fact 2: Insulation serves to both prevent heat loss in the winter and heat gain in the summer.

Answer:
Head hair is a type of insulation.