instruction:
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.
question:
Fact 1: Plants release oxygen during the day but not during the night. 
Fact 2: Plants include blue pine, hemlock, spruce and oak.
answer:
Blue pine releases oxygen during the day but not during the night.


question:
Fact 1: a laser is used for producing light. 
Fact 2: Light contains energy.
answer:
A laser is used for producing energy.


question:
Fact 1: lack of moisture in the air causes low amounts of rainfall. 
Fact 2: Areas of moderate and low rainfall are drought prone.
answer:

drought prone areas experience a lack of moisture in the air.