Students hypothesized that adding lactose to a sixth test tube would produce the greatest amount of carbon dioxide.
This is because lactose is a sugar molecule that is the food source for the yeast.
Fermentation is a metabolic pathway that occurs anaerobically, meaning in the absence of oxygen (O2). It includes the process of glycolysis with some extra reactions which make alcohol.
The value of the unknown number is 10.5.
Let the unknown number = x
When 20 is subtracted from the number and the result is squared which is equal to the square of the unknown number minus 20:
(x - 20)² = x² - 20
<em>expand the equation;</em>
x² - 40x + 400 = x² - 20
<em>collect similar terms together;</em>
x² - x² - 40x = -20 - 400
-40x = -420

Thus, the value of the unknown number is 10.5.
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