Question

multiple choice question scientists on the international space station want to study how microgravity affects plants. why do these scientists use variables? variables allow scientists expectations to change how the results are analyzed. variables help scientists keep track of all the factors that affect plant growth. variables offer a testable explanation for a problem using what the scientists know.

Explanation:

In scientific experiments, variables are used to formulate testable explanations. Scientists manipulate and observe variables to understand cause - and - effect relationships. Here, they want to study the effect of microgravity on plants, and variables help in creating a testable hypothesis and experimental design.

Answer:

Variables offer a testable explanation for a problem using what the scientists know.