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: Urine leaves the body through a sphincter in the process of urination. 
Fact 2: Fluids in the urine eliminate metabolic waste products.
[A]: Metabolic waste products can leave the body through a sphincter.


[Q]: Fact 1: Platypus females lay their eggs in a burrow. 
Fact 2: Like the platypus, it is an egg laying mammal.
[A]: some mammals lay their eggs in a burrow.


[Q]: Fact 1: eyes are used for seeing by animals by sensing light. 
Fact 2: Vision is out the eyes.
[A]:
vision is used for seeing.