A person's breathing rate can be affected biologically if they have shortness of breathe, asthma, in some cases anxiety.
Environmental would be weather, if it is very cold their breathing rate will not be the same with moderate temperature.
Internal factor would be lungs. If a person has smoked or has any sort of lung damage or disorder this will affect whether the person has a normal breathing rate
Answer: STOMACH BUG OR STOMACH FLU
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Answer: Muscular strength
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