Im not positive but I think it's b or c
<span>the outer ear is used to collect sound waves.
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Answer:
sour, corrosive
Explanation:
An acid is a substance that donates hydrogen ions. Because of this, in an acidic solution there are more hydrogen ions than hydroxide ions. This means the more acidic a food is, the more hydrogen ions are available to trigger the sour taste receptors. A base is a substance that accepts hydrogen ions.
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