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: Blood pH may become unbalanced if the rate of breathing is too fast or too slow. 
Fact 2: Acidity is measured with a pH meter or with pH paper strips.

Answer: Blood acidity may become unbalanced if the rate of breathing is too fast or too slow.


Question: Fact 1: Mollusks reproduce sexually. 
Fact 2: Some mollusks have a shell.

Answer: some animals with shells reproduce sexually.


Question: Fact 1: hearing is used for sensing sound by animals. 
Fact 2: Animals utilize sound to localize mates and avoid approaching predators.

Answer:
Animals use their sense of hearing to avoid approaching predators.