In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

Question: How many forces do objects on earth have acting on them at all times? Answer: two
Objects on earth have two forces acting on them at all times.

Question: What type of light is composed of many rays having random polarization directions? Answer: unpolarized light
Unpolarized light type of light is composed of many rays having random polarization directions.

Question: What type of reaction causes two substances to combine to make a single substance? Answer: composition reaction

Composition reaction type of reaction causes two substances to combine to make a single substance.