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: a plant requires water to grow. 
Fact 2: Clouds form by the condensation of water vapor.

A: a plant requires Clouds to grow.
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Q: Fact 1: Plasma cells are activated B cells that secrete antibodies. 
Fact 2: Antibodies are produced by plasma cells.

A: activated B cells secrete antibodies.
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Q: Fact 1: a scale is used for measuring weight. 
Fact 2: Weight Weaning weight is expressed in pounds.

A:
A scale is used for measuring pounds.
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