The answer is negative controls. These are groups where no phenomenon is probable. They ensure that there is no effect when there should be no effect. Where there are only two possible outcomes, e.g. positive or negative, if the treatment group and the negative control both produce a negative result, it can be concluded that the treatment had no effect. If the negative control group and the treatment group both yield a positive result, it can be inferred that a puzzling variable is involved in the occurrence under study, and the positive results are not only due to the treatment. In other examples, outcomes might be measured as lengths, times, percentages, and so forth.
Answer:
This statement is true, as the inner core is the most dense layer of the earth.
<span>Glucose is the human body's key source of energy as it provides energy to all the cells in our body. Glucose also is critical in the production of proteins, lipid metabolism and is a precursor for vitamin C production.</span><span><span>Glucose is the sole source of fuel to create energy for all brain and red blood cells.</span> The availability of glucose influences many psychological processes. When glucose levels are low, psychological processes requiring mental effort l(self-control, critical thinking and decision-making) become impaired.
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