In a scientific investigation, what is the name for a prediction that can be tested?

Hypothesis

Explanation:

A scinetific investigation is a inquiry to answer questions related to natural phenomena or event. A hypothesis is a predicted statement which is based upon few evidences which are required to be proved using suitable experimental procedures which can help in determining the cause of natural phenomena or event.

the correct answer is:

a population changes in response to a change in the environment.

blue stars have the highest surface temp

stellar distances are usually expressed in light-years

the measure of a star's brightness is called magnitude

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