Because their soft tissue and bones decay or get eaten before a fossil can be made.
Explanation:
Scavenging refers to carnivores feeding on carrion.
If I would have to make a good guess, I would choose A.
Lipids are a group of organic compounds including fats, phospholipids, and steroids.
Lipids are a group of organic compounds that do not dissolve easily with water. Lipids include fats, oils, monoglycerides, diglycerides, triglycerides, phospholipids, hormones, vitamins (such as vitamins A, D, E, and K), and steroids. Lipids functions by storing energy for organisms, as chemical messengers between cells, tissues, and organs, and they also function as structural parts of cell membranes.
Answer:
Students who take a PE class and who will be eating sugary snacks before PE.
Explanation:
The control variable (or control group) is an experimental element which is constant or unchanged throughout the course of the experiment.
The option "students who take PE class and who will be eating sugary snacks before PE" will remain unchanged and constant because the whole point of the experiment is to see the effects on students performance in PE after eating sugary snacks.
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