Mark the letter A, B, C, or D on your answer sheet to indicate the cor

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.    

Water always boils when you heat it long enough.

• A. A. If heated long enough, water boils.
• B. B. If water is heated long enough, it boils.
• C. C. If you heat water long enough, it boils.
• D. D. All are correct.

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