An error is that the scientist did not control their variables. They had one group of people playing the game at 6, and another group playing at 12. This means that other things might have affected the scores other than what was being tested, which was caffeine.
This is called asexual reproduction.
Answer:
Cnidarians represent a more complex level of organization than Porifera. They possess outer and inner tissue layers that sandwich a noncellular mesoglea. Cnidarians possess a well-formed digestive system and carry out extracellular digestion.
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The answer to the question stated above is letter b. <span> <span>a meteor or asteroid colliding with Earth
</span></span> <span>The mass extinction at the end of the Mesozoic Era was caused by </span>a meteor or asteroid colliding with Earth. This was said to happen about 65 million years ago.
Macronutrients are nutrients that provide calories or energy. Nutrients are substances needed for growth, metabolism, and for other body functions. Since “macro” means large, macronutrients are nutrients needed in large amounts. There are three macronutrients:CarbohydrateProteinFatso its not B
There are three<span> primary types of </span>antioxidants<span> found in nature. These include phytochemicals, vitamins, and enzymes.
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So not C.
<span>The three micronutrients are vitamins, minerals, and water.
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So not A.
And that leaves you with D.(D is the correct answer for num.1)