I think the answer is frequency if I remember correctly
Answer:
B.) Diffusion
Explanation:
Since this is oxygen, not water, and it is going from an area of high concentration to low, it is moving with its concentration gradient, it would be diffusion. If it were water, not oxygen, then it would be osmosis, and lastly, if it were moving from an area of low to high concentration, that would be active transport. Semipermeability is a characteristic of cell membranes, not a method of movement.
MASS: because it is the measure of the amount of matter in an object
Answer: They are also known as <u>B. tranquilizers</u>
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Hope this helps!