An Experimenter Tests the Hypothesis That Physical Exercise Improves People's

question 296

Multiple Choice

An experimenter tests the hypothesis that physical exercise improves people's mood.Subjects in the experimental group participate on Monday and Tuesday and those in the control group on Wednesday and Thursday.What is the independent variable?

• A) the hypothesis
• B) the day of the week
• C) the exercise
• D) the mood (degree of happiness)

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Definitions:

Third Energy Level

The third energy level in an atom is the third shell that surrounds the nucleus, where electrons can be found.

Protons

Positively charged particles found within atomic nuclei that, along with neutrons, define the atomic mass.

Electrons

Subatomic particles with a negative charge, orbiting the nucleus of an atom and involved in chemical bonds and electricity.

Hydrogen Bonds

Weak bonds that form between a hydrogen atom in one molecule and a more electronegative atom, such as oxygen or nitrogen, in another, playing critical roles in the structure of DNA and proteins.