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: Scientists who find and study fossils are called paleontologists. 
Fact 2: Fossil fuels are the fossilized remains of prehistoric animals and plants.

Answer: paleontologists study the remains of plants.


Question: Fact 1: the volume of an object can be used to describe the size of that object. 
Fact 2: Size of waves depends on the mass and volume of the object that fell into the water.

Answer: The volume of an object depends on the mass of the object.


Question: Fact 1: Some viruses can cause cancer. 
Fact 2: Human papillomavirus vaccine is aimed at the cause of most cases of cervical cancer.

Answer:
A vaccine against a virus can protect against cervical cancer.