TASK DEFINITION: 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.
PROBLEM: Fact 1: a sifter is used for separating mixtures. 
Fact 2: For the seasoning mixture combine all ingredients.

SOLUTION: a sifter is used for separating combined ingredients.

PROBLEM: Fact 1: having no natural predators increases population size. 
Fact 2: Any population has the potential to produce more offspring than the environment can support.

SOLUTION: Having no natural predators increases potential to produce more offspring than the environment can support.

PROBLEM: Fact 1: the volume of an object can be used to describe the size of that object. 
Fact 2: Volume is the amount of space occupied by an object.

SOLUTION:
the amount of space occupied by an object can be used to describe the size of that object.