<u>Answer</u>: an all or none response
According to the all-or-none law, it a certain threshol is crossed by a stimulus' strenght, it will cause a response in the nerve cell or muscle fiber. However, the strenght of the response will always be the same and will not vary with different stimulus strengths. The only requirement is for the threshold to be crossed.
Protons and neutrons. But since the protons outweigh the neutrons. so your answer is d
Yes, human activities are a significant cause of the increase in the amount of Carbon dioxide in the atmosphere.
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Explanation:</u></h3>
The increasing amount of 
is a big problem in today's world for the atmosphere. Human activities are playing a vital role in the rise in . Carbon emission is majorly happening because of pollution. The pollution by vehicle, wax factories, chemical factories, etc. also, some other kinds of Carbon emission activities are there like burning coal and plastic produces Carbon in very high amount and this Carbon directly mix into the atmosphere.
Due to the increase in , both natural and agricultural ecosystems are suffering. causes air pollution, and because of that, the quality of crops is declining day by day. Also, the natural vegetation is struggling as the rainwater is also not pure; the amount of acidic content in natural rain is increasing per year. All these activities are leading towards global warming, which one day will bring our earth to an end. So it is imperative to take some severe legal measures to save the environment and decline the amount of producing.
