A) combustion of fossil fuels
<span>Two characteristics of leisure travelers is that they often will travel by car, and generally they take shorter trips. The whole idea of leisure travel is to take a little vacation from the chores of everyday life. It is generally characterized as people staying in nice hotels, relaxing, touring, and experiencing something new, fun and exciting.</span>
Ring of fire, hope this helps.
Answer and Explanation:
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The experiment done by Meselson and Stahl demonstrated that DNA replicated semi-conservatively, meaning that each strand in a DNA molecule serves as a template for synthesis of a new, complementary strand. Although Meselson and Stahl did their experiments in the bacterium E.