<span>A portable fire extinguisher can save lives and property. Nevertheless, it has limitation for it is only indicated to put off small fire. It is appropriate to use portable fire extinguisher when the room temperature is only slightly increased. In addition, one must decide to use portable fire extinguisher to fight a small fire only if the room is not filled with smoke and the fire is not growing. Therefore, the answer is B.
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A virus is a small infectious agent that replicates only inside the living cells of other organisms. Viruses can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea.
Diet and exercise is the answer.
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