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: Reproduction is the process by which organisms give rise to offspring. 
Fact 2: Sex equals reproduction.

Answer: sex is the process by which organisms give rise to offspring.


Question: Fact 1: changes in the pH of soil can cause plants to die. 
Fact 2: Sulfur lowers pH in soil.

Answer: Adding sulfer to soil can cause plants to die.


Question: Fact 1: volcanic ash in the atmosphere decreases the temperature by blocking the sun. 
Fact 2: Volcanic activity was responsible for the rising temperatures.

Answer:
Volcanic activity raises temperature.