The best precaution against carbon monoxide poisoning is to keep air moving through the boat.
Carbon monoxide is a potentially deadly gas that is produced any time a carbon-based fuel burns. If you suspect carbon monoxide poisoning you must do the following: open doors and windows, turn off gas appliances. To determine if a person is poisoned by carbon monoxide you may look for the following signs and symptoms: dull headache, weakness, dizziness, nausea or vomiting, shortness of breath, confusion, blurred vision, loss of consciousness.
Answer:

Option B is correct.
Explanation:
There are <u>thousands</u> of proteins and only 20 amino acids.
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