An independent variable is: A. Remain the same to make an experiment a fair test.
O B. Measured to show the effect of a change.
C. Collected to draw conclusions.
D. Changed to test a hypothesis.

Which of the following statements best distinguishes a hypothesis from a theory? a. theories are hypotheses that have been proved. b. hypotheses are guesses; theories are correct answers c. hypotheses usually are relatively narrow in scope; theories have broad explanatory power. d. theories are proved to be true; hypotheses are often contradicted by experimental results.