Life and death are complex things. Life is the existence of something and death is the end. They go hand in hand. Without one you cannot have the other. To live means to die and to die means you have lived.
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Cos they were created like that
The answer is Vitamin C otherwise known as Ascorbic acid. It is naturally present in some foods, added to others and available in dietary supplement. Fruits and vegetables are the best sources of vitam C. Citrus fruits, tomatoes and tomato juice and potatoes are major contributors of vitamin C.
The answer should be the refractory period